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JEAN *. BILL LANE 

HORTICULTURAL LIBRARY 





Copyright by Hartsook 






LUTHER BURBAXK 



HOW PLANTS ARE TRAINED 
TO WORK FOR MAN 

BY LUTHER BURBAXK Sc. D 



PLAXT BREEDING 



VOLUME I 




EIGHT VOLUMES ILLUSTRATED 

PREFATORY NOTE BY DAVID STARR JORDAN 



P. F. COLLIER & SON COMPANY 
NEW YORK 



'Jniv Librarv UC Santa Cruz 1999 



Copyright, 1914 

BY THE LUTHER BURBANK SOCIETY 
All rights reserved 

Copyright, 1914 

BY THE LUTHER BURBANK SOCIETY 

Entered at Stationers' Hall, London 

All rights reserved 

Copyright, 1915 

BY THE LUTHER BURBANK SOCIETY 

Entered at Stationers' Hall, London 

All rights reserved 

Copyright, 1921 
BY P. F. COLLIER & SON COMPANY 

\T \NUFACTURED IN U. S A 



LIST OF ILLUSTRATIONS 

VOLUME I 
LUTHER BURBANK .... , : Frontispiece 

PAGE 

A CROSS OF ORANGE AND LEMON ... 40 

THORNLESS BLACKBERRY BLOSSOMS ... 44 

A LARGE, LATE-BEARING RED SEEDLING CHERRY 50 

ORDINARY FIELD CORN AND ITS TINY PARENT 62 

AN EXPERIMENT IN CORN 66 

ARMORED AGAINST ITS ENEMIES .... 70 

IMPROVED AND WILD CACTI STILL BEAR LEAVES 76 

CONTRASTING TYPES OF CACTUS .... 80 

VESTIGIAL LEAVES . 86 

A BEAUTIFUL FLOWERING CACTUS . . , 90 

THIS PLANT EATS AND DIGESTS INSECTS . 104 

A NEW PLUM AND ITS WILD ANCESTOR . . 108 

THE BURBANK POTATO 114 

THE GERANIUM READY TO RECEIVE POLLEN . 120 

A POLLEN-LADEN BEE 124 

ARUM DRACUNCULUS A FLY-LOVING FLOWER 130 

THE COCONUT'S THREE EYES 138 

THE DEVIL'S CLAW I 140 

THE DEVIL'S CLAW II 142 

THE DEVIL'S CLAW III 144 

THE SNOWBALL CULTIVATED AND WILD . . 152 

SOME FORMS OF CORN .... ... . . 162 

VARIATION IN CORN SEED M ..... 166 

RAINBOW CORN 170 

Vol. 1 Bur A 1 



2 LIST OF ILLUSTRATIONS 

PAGE 

CALIB'ORNIA POPPY (Eschscholtzia) . . . 176 

A BURBANK BONFIRE 180 

THE CALIFORNIA POPPY TURNED CRIMSON . 184 

THE CALIFORNIA POPPY TURNING WHITE . 188 

STAR CHILEAN WILD FLOWER .... 192 

A BED OF CHINESE PINKS 196 

SAMPLE OF AN IMPROVED GLADIOLUS ... 200 

AT THE DOOR 208 

THE NEW AMARYLLIS AND ITS PARENTS , . 214 
MORE THAN FIVE HUNDRED KINDS ON ONE 

TREE 218 

Two SEEDLING TYPES OF CHERRIES ... 222 

SOME OF THE 400 COME TO JUDGMENT . . 226 

SOME HYBRID BLACKBERRY CANES . . . 238 

VARIATIONS IN WALNUTS 248 

A HEAVY-BEARING SEEDLING 254 

THE PLUM'S PERISHABLE BLOOM .... 264 

WHITE AND CRIMSON SIDE BY SIDE . . . 294 

THE SHASTA DAISY . . . . .... 302 

THE SHASTA DAISY AND Two OF ITS RELATIVES 308 
SHASTA DAISIES CURIOUS TUBULAR RAY 

FLOWERS 314 

A BEAUTIFUL LACINIATED TYPE .... 320 

THE CRYSTAL WHITE, So CALLED .... 330 
SIGNS OF SUCCESS LARGER YELLOW-WHITE 

BERRIES 338 

WHITE BLACKBERRIES AS THEY GROW . . 346 

VOLUME II 
THE FRAGRANT CALLA .... Frontispiece 

THE SPADIX OF ONE OF THE CALLA LILIES . 12 

HYBRID CALLAS 18 



LIST OF ILLUSTRATIONS 3 

PAGE 

STRAWBERRIES SHOWING VARIATION ... 28 

A TYPICAL STONELESS PLUM 38 

DOUBLE SEEDS SOMETIMES TAKE THE PLACE 

OF A STONE 44 

THE ORIGINAL AND THE FINISHED PRODUCT 56 

A SIXTEEN- YEAR-OLD "ROYAL" WALNUT . . 62 

WOOD OF THE "ROYAL" WALNUT .... 66 

"PARADOX" WALNUT WOOD Two INCHES IN 

DIAMETER EACH YEAR 70 

VARIATION IN HYBRID WALNUT LEAVES . . 76 

HYBRID WALNUTS 80 

A GRAFTED WALNUT TREE 84 

A TYPICAL PLANT OF GIANT WINTER RHUBARB 92 

READY FOR SHIPMENT 106 

THE GIANT CHERRY 116 

THE ABUNDANCE CHERRY 128 

THE SUGAR PRUNE AND ITS PARENTS . . . 140 

A Luscious FRUIT . 150 

POTATO SEED BALLS 168 

LEAVES OF STRAWBERRY-RASPBERRY HYBRIDS 174 

COMPLETE KIT OF POLLENIZING TOOLS . . 188 

ONE OF THE ORIENTAL PEARS 194 

AMERICAN PEARS WITH BLENDED HEREDITIES 198 

TEN CORN VARIATIONS 202 

CORN TEOSINTE HYBRIDS SEVENTEEN FEET 

HIGH 206 

CORN SELF - POLLINATED AND CROSSED WITH 

TEOSINTE 210 

SOME STEMS OF BLACKBERRY-RASPBERRY HY- 
BRIDS 218 

A SHIRLEY POPPY SHOWING REPRODUCTIVE 

ORGANS .... 230 



4 LIST OF ILLUSTRATIONS 

PAGE 

POLLEN-BEARING PUMPKIN BLOSSOM . . . 236 

SEED-BEARING PUMPKIN BLOSSOM .... 240 

A POLLEN-BEARING GRAPEVINE .... 244 

STRAWBERRY BLOSSOM (ENLARGED) . . . 250 
THE STIGMATIC SURFACE OF A POPPY MUCH 

ENLARGED ra 254 

CROSS SECTION OF THE CACTUS BLOSSOM . r . 260 
RASPBERRY BUSH AFTER POLLINATION . r . 264 
"FLAT" WITH LAYER OF GRAVEL . . . . 270 
"FLAT" PARTLY FILLED WITH PREPARED COM- 
POST 274 

A COLD FRAME 282 

PROTECTING SEEDLINGS FROM THE BIRDS . . 290 

YOUNG PLANTS AWAITING SELECTION . . . 294 

COMPLETE GRAFTING OUTFIT 300 

CUTTING STOCK FOR WHIP GRAFT .... 310 

A SIDE GRAFT IN POSITION 314 

CROWN OR BARK GRAFT 320 

CUTTING THE BARK TO RECEIVE A BUD . . 324 

THE BUD GRAFT COMPLETED . . . . . 328 

READY FOR SHIPMENT . . . . , ; ., . 338 

A HYBRID EVERGREEN ...... M 346 

VOLUME III 
AN APPLE GRAFT ONE YEAR OLD . Frontispiece 

SEEDLESS GRAPES 12 

A BASKET OF PLUMS 24 

AN EARLY DIAGRAM OF TREE GRAFTS . . 36 

RESELECTING SELECTED CACTUS SEEDLINGS . 42 

GRAFTING RECORD 46 

RIPENING RECORD 50 



LIST OF ILLUSTRATIONS 5 

PAGE 

ROSE CUTTINGS DEVELOPED BY SELECTIVE 

BREEDING 64 

THE WICKSON PLUM 78 

SANTA ROSA PLUM 84 

GETTING COLOR INTO THE PEAR .... 92 

SHIRO PLUMS 116 

A CURIOUS FRUIT 120 

NAMELESS SEEDLINGS 128 

SOME CURIOUS SHORT-STEMMED HYBRIDS . 138 

IMPROVED HOLLY CHERRY 144 

THE HOLLY CHERRY 148 

A PATRICIAN 158 

DISSIMILAR TWINS 168 

AN IDEAL PEAR 176 

THE NECTARINE 184 

THE LEADER PEACH . . . . . . . 188 

A NEW SEEDLING NECTARINE ..... 194 

THE EXQUISITE PEACH 200 

A BEAUTIFUL SEEDLING APPLE .... 210 

THE CRAB APPLE ....... f 216 

THREE SEEDLING APPLES .' 220 

NAMELESS BEAUTIES 224 

GETTING ON IN THE WORLD 228 

HALF-SWEET, HALF-SOUR APPLE .... 232 

VAN DEMAN QUINCE 238 

PINEAPPLE QUINCE 244 

THE MEDLAR A COUSIN OF THE QUINCE . 252 

APRICOT AND SEED 264 

THE APRICOT 270 

A BUNCH OF THE COMMON LOQUATS . . 274 

IMPROVED LOQUATS 278 

IMPROVED LOQUATS .... 282 



6 LIST OF ILLUSTRATIONS 

PAGE 

FRUIT OF THE GUAVA 290 

SWEET LEMONS 300 

SEEDLING POMEGRANATE FRUITS .... 308 

THE CLIMAX PLUM 316 

BEAUTY PLUM FRUITS , 320 

THE BLOOD PLUM SATSUMA 324 

TYPE OF SELECTED BLOOD PLUM SEEDLING . 328 

A KELSEY-SATSUMA HYBRID 332 

NINE VARIETIES OF CROSSBRED PLUMS . . 336 

A KELSEY-BURBANK HYBRID 344 

JORDAN PLUM 348 

VOLUME IV 
THE FRUIT OF THE BURBANK PLUM Frontispiece 

THE LATE SHIPPER .... ; . ; ... 14 

PRUNE D'AGEN FRUIT 28 

THE SUGAR PRUNE . . . 32 

THE SPLENDOR PRUNE ....... 36 

PRUNE DRYING IN CALIFORNIA 40 

THE STANDARD PRUNE ........ 44 

THE CONQUEST PRUNE . . . . ... 48 

ONE OF THE PLUMCOTS ... . ... . ;.. . 60 

A SUPERIOR PLUMCOT 68 

PLUMLIKE PLUMCOT 104 

PURPLE-LEAVED PLUM WITH FRUIT . . . 118 

GLOBE PLUM FRUITS 128 

FIRM SWEET PLUM FRUITS 134 

THE APPLE PLUM 140 

ANOTHER VIEW OF THE APPLE PLUM . . 148 

A SEEDLING CRIMSON-LEAFED PLUM . . . 156 

AN EXAMPLE OF UNIFORM RIPENING 164 



LIST OF ILLUSTRATIONS 7 

PAGE 

A GOOD ROOT SYSTEM 174 

THE ODD PLUMCOT 182 

CHERRY PLUMCOT 186 

SWEET PLUMCOT 190 

ONE OF THE NEW PLUMCOTS 194 

CLUSTER OF APEX PLUMCOTS 198 

ANOTHER PLUMCOT 202 

THE BURBANK PLUMCOT 206 

THORNLESS BLACKBERRY AND THE RECREANT 

SEEDLING 212 

ONE OF THE NEW THORNLESS BLACKBERRY 

CLUSTERS 220 

THE FAMILIAR BLACKCAP RASPBERRY . . 236 

THE PRIMUS BERRY 242 

THE PHENOMENAL BERRY 250 

AN INTERESTING HYBRID 256 

A SAMPLE SEEDLING STRAWBERRY . . . 264 

AN ALL-SUMMER BEARER 270 

EVERBEARING STRAWBERRIES 274 

ANOTHER PERPETUAL VARIETY .... 278 

YET ANOTHER HYBRID VARIETY .... 282 

SUNBERRIES 290 

LEAF VARIATIONS IN A HYBRID .... 306 

HAWAIIAN RASPBERRIES 316 

THE BUFFALO BERRY 322 

INTERESTING HYBRID BERRIES 330 

A NEAR VIEW OF Two BOXES OF BERRY 

SEEDLINGS 342 

GRAPES OF THE CONCORD TYPE .... 352 

SEEDLING SYRIANS 356 

A MAMMOTH CLUSTER 360 

UNPRODUCTIVE BUT MERITORIOUS 364 



8 LIST OF ILLUSTRATIONS 

PAGE 

SMALL CLUSTER OF A FINE SEEDLING . . 368 

THE EL^EAGNUS OR GOUMI BERRY ... 380 

VOLUME V 
A BURBANK STRAWBERRY . . . Frontispiece 

A CACTUS FRUIT THAT IMITATES THE PEAR 10 

CACTUS FRUIT ON THE SLAB 14 

A GOOD SPECIMEN 18 

A WELL-PROPORTIONED FRUIT 20 

FRUIT OF A CHILEAN MYRTLE .... 28 

THE FRUIT OF THE STRAWBERRY TREE . . 32 
FRUIT OF ONE OF MY GREATLY IMPROVED 

VARIETIES OF MOUNTAIN ASH ... 36 

THE RESULT OF EDUCATION 42 

A CLUSTER OF THE NEW WHITE ELDER- 
BERRIES 50 

COLOR VARIATIONS IN THE CANES OF THE 

HYBRID BLACKBERRIES 56 

THE STEM FINALLY SELECTED .... 62 

BABY PLANTS 74 

A BEAUTIFUL THIEF 82 

ILLUSTRATING LEAF STRUCTURE .... 88 

WHERE THE TREE is ALIVE 94 

COMPOST FOR YOUNG PLANT FOOD . . . 102 

SOME EXPERIMENTAL GOURDS 108 

SOME GOURDS FROM AUSTRALIA .... 114 

THE FAMILIAR BEET 118 

ANOTHER OLD FRIEND 122 

PARSNIPS 12 

COWPEAS UNDER CULTIVATION 134 

SHOWING VARIATION IN BEANS 146 



LIST OF ILLUSTRATIONS 9 

PAGE 

A STRIPLING FROM THE TROPICS .... 152 

FRUITS OF A TOMATO HYBRID 160 

POTATOES WITH A STRANGE HISTORY . . 166 

TRANSPLANTING SELECTED SEEDLINGS . . 172 

A SOUTH AMERICAN ALLIUM 194 

A NEW ALLIUM 202 

A BASKET OF BURBANK PEPPERS .... 210 

BURBANK PEPPERS 214 

ARTICHOKES 220 

HALF-OPENED ARTICHOKE BLOSSOM ... 224 

A WILD ARTICHOKE 228 

AN IMPROVED ARTICHOKE 234 

FLOWER AND FRUIT ON THE SAME PLANT . 254 

A BED OF SELECTED CROSSBRED CAMASSIAS . 264 

A WIDE RANGE OF VARIATION .... 270 

CAMASSIA BLOSSOMS 274 

THE WILD CAMASSIA . 280 

WILD HIGH ANDES POTATOES 288 

SOME SELECTED SEEDLINGS 294 

A FINE NEW EARLY POTATO 300 

A FREAK EAR OF CORN 314 

SECTIONS OF RAINBOW CORN LEAVES . . 322 

THREE FINE TYPES OF CORN 330 

WHEAT GERMINATING ON ICE 344 

A GLIMPSE AT MY WHEAT EXPERIMENTS 348 



VOLUME VI 

ARTIFICIAL RAIN IN MR. BURBANK'S 

GARDEN Frontispiece 

RESULTS OF WHEAT EXPERIMENTS ... 14 
A SHEAF OF OATS 18 



10 LIST OF ILLUSTRATIONS 

PAGE 

SAMPLE HYBRID SUNFLOWER 22 

THE FLAX PLANT 50 

COTTON FLOWER AND SEED HEAD .... 58 

SUGAR CANE TASSELS 70 

VARIETIES OF SORGHUM 78 

A HOP-FIELD VISTA 84 

SUGAR BEETS AT THE FACTORY .... 90 

THE CANDLE CACTUS 98 

THE GRAVITY CACTUS 104 

THE PROLIFIC CACTUS 110 

YOUNG ROYAL CACTUS PLANTS .... 116 

THE HEMET CACTUS 122 

THE MELROSE CACTUS 128 

SPINELESS CACTUS SHOWING Six MONTHS' 

GROWTH 134 

A FRUIT COLONY 140 

CACTUS BLOSSOMS 148 

CACTUS CANDY 156 

A CACTUS -SLAB FAN 164 

PAMPAS GRASS 180 

VARIATION IN COLOR AS WELL AS IN FORM 200 

PERENNIAL PEAS 210 

A YELLOW TRITOMA OR "RED-HOT POKER" . 218 

THE BURBANK ROSE 228 

A NEW YELLOW RAMBLER 232 

ROSES AT SEBASTOPOL 236 

GLIMPSE IN THE PROVING GROUND . . . 240 

A MAMMOTH BOUQUET 244 

THE CORONA ROSE 248 

GIANT AMARYLLIS 252 

KEMANTHUS BLOSSOMS 256 

SEEDLINGS OF THE BELLADONNA LILY 260 



LIST OF ILLUSTRATIONS 11 

PAGE 

A DOUBLE AMARYLLIS 264 

A BURBANK AMARYLLIS 268 

ONE OF THE NEW CRINUMS 272 

SEED PODS OF THE CRINUM 276 

A NEW SHIRLEY POPPY 282 

ANOTHER NEW SHIRLEY POPPY .... 288 

ANOTHER NEW POPPY 294 

A HYBRID POPPY 298 

THE BURBANK ART POPPIES 302 

A SEMIDOUBLE DAISY 310 

LACINIATED PETALS 316 

A BOUQUET OF SHASTAS 322 

A WHITE GLADIOLUS 328 

A PRIMITIVE TYPE OF DAHLIA .... 340 

A COMMON TYPE OF THE MODERN DAHLIA 348 



VOLUME VII 
LARGE SIZE AND COMPACT GROWTH Frontispiece 

A NEW GIANT GLADIOLUS 12 

ONE OF TEN THOUSAND VARIATIONS ... 18 

AN UNUSUAL COLOR IN THE GLADIOLUS . 24 

A SAMPLE GANDAVENSIS PRIMULINUS HYBRID 30 

A SEEDLING CANNA 36 

ANOTHER SEEDLING CANNA 42 

GIANT AND DWARF CALLAS 48 

THE LEMON GIANT CALLA 52 

THE SIBERIAN LILY 58 

SOME OF MY NEW SEEDLING WATSONIAS . 66 

A SPECTACULAR IRIS 80 

A LUXURIOUS TYPE 90 

SELECTED CHILEAN IRIS 102 



12 LIST OF ILLUSTRATIONS 

PAGE 

A JAPANESE IRIS 112 

SEEDLING JAPANESE IRIS 124 

A NEW EVENING PRIMROSE THE AMERICA . 134 

HYBRID TIGRIDIAS 144 

ANOTHER HYBRID TIGRIDIA 148 

SEEDLING TIGRIDIAS 152 

A BLUE TIGRIDIA 158 

BURBANK VERBENAS 166 

MORE BURBANK HYBRID VERBENAS . . . 170 

ONE OF THE FRAGRANT ONES 174 

AUSTRALIAN STAR FLOWER 188 

A PLANT OF AUSTRALIAN STAR FLOWER . 192 

A HYBRID CRINUM 196 

A HYBRID EVERBLOOMING POPPY .... 202 

STILL ANOTHER HYBRID POPPY .... 206 

IMPROVED HYBRID LARKSPUR 214 

MORE HYBRID LARKSPURS 218 

EDUCATING THE CALENDULA 222 

A CALENDULA OF REAL DISTINCTION . . 226 

THE VARIEGATED NEGUNDO 232 

FLOWERS OF THE TECOMA 258 

SPANISH BROOM 268 

A FRITILLARIA 274 

DlERAMA PULCHERRIMA 280 

LARKSPURS WITH WONDERFUL COLORING . . 286 

A BEAUTIFUL HYBRID LARKSPUR .... 292 

THE BOTTLE-BRUSH BUSH 298 

A SELECTED NIGHT-BLOOMING CEREUS . . 312 

THE ALMOND AND ITS RELATIVES . . . 326 

SELECTED ALMONDS 330 

SOME MAMMOTH SPECIMENS 334 

MEATS OF SELECTED ALMONDS 338 



LIST OF ILLUSTRATIONS 13 

PAGE 

ALMONDS GROWN IN PEACHES .... 342 

HYBRID WALNUTS 358 

THE ROYAL WALNUT . . . 372 



VOLUME VIII 
SANTA ROSA NUT MEATS . . . Frontispiece 

A DWARF CHESTNUT TREE 10 

A BASKET OF CHESTNUTS 16 

THE PAPER SHELL ON THE TREE . . . .30 

SANTA ROSA WALNUTS 36 

PARENTS AND OFFSPRING 44 

SIX-MONTHS-OLD CHESTNUT TREE IN BEARING 54 

YEARLING CHESTNUT TREE IN BEARING . . 58 

A SIX-MONTHS-OLD CHESTNUT TREE . . 62 

BUR AND CATKIN 66 

WELL PROTECTED . 70 

CHESTNUTS IN THE BUR 74 

HICKORY NUTS 80 

A PECAN TREE 84 

A VARIETY OF TROPICAL NUTS .... 88 

CHINQUAPINS AND CHESTNUTS .... 92 

THE WILD NUTMEG 104 

OLIVE TREES 116 

THE CALIFORNIA CHINQUAPIN AS AN ORNA- 
MENTAL TREE 130 

THE VARIEGATED Box ELDER 138 

AN ACACIA TREE IN BLOOM 144 

A YOUNG SEQUOIA GIGANTEA 152 

THE LARGEST TREE IN THE WORLD . . . 158 

YELLOW PINE 162 

THE JUDAS TREE OR RED-BUD . 166 



14 LIST OF ILLUSTRATIONS 

PAGE 

THE HYBRID ELM 170 

OLIVE Ross BURBANK, LUTHER BURBANK'S 

MOTHER 184 

LUTHER BURBANK'S BIRTHPLACE .... 202 

THE OLD HOMESTEAD AS IT Now APPEARS . 212 

MRS. LUTHER BURBANK 224 

LUTHER BURBANK AT THE AGE OF TWENTY- 
FIVE 246 

MY FIRST ADVERTISEMENT 252 

VIEW IN THE SANTA ROSA GARDENS . . . 258 

MIDSUMMER'S VIEW 266 

A SIMPLE BUT IMPORTANT EQUIPMENT . . 274 

SOIL-STIRRING IMPLEMENTS 280 

SEEDS IN THE GREENHOUSE 286 

CLEANING SEEDS 292 

A COLLECTION OF SIEVES 298 

MARKING Rows FOR PLANTING .... 304 

PERMANENT LABELS 312 

AN EFFECTIVE IMPLEMENT 318 

HYBRIDS AND PARENTS 324 

UNNAMED BEAUTIES 330 

TIGRIDIA SEEDS AT WHOLESALE .... 336 

MIDSUMMER AT SANTA ROSA 342 

BACK VIEW OF MY HOME SHOWING VINES 354 

TROPICAL LUXURIANCE 362 

A STRIKING CONTRAST IN SEEDLINGS 370 



CONTENTS 

PAGE 

A WORD TO THE READER. Luther Bur- 
bank 17 

PREFATORY NOTE. David Starr Jordan . 21 

FUNDAMENTAL PRINCIPLES OF PLANT 

BREEDING 37 

EVOLUTION AND VARIATION WITH THE 

FUNDAMENTAL SIGNIFICANCE OF SEX 53 

How PLANTS ADAPT THEMSELVES TO 

CONDITIONS 69 

TWENTY-THREE POTATO SEEDS AND WHAT 

THEY TAUGHT 93 

No Two LIVING THINGS EXACTLY 

ALIKE 117 

THE RIVALRY OF PLANTS TO PLEASE Us 147 

LET Us Now PRODUCE SOME NEW COLORS 

IN FLOWERS 175 

15 



16 CONTENTS 

PAGE 

SHORT CUTS INTO THE CENTURIES TO 

COME 205 

How FAR CAN PLANT IMPROVEMENT Go? 233 
MARVELOUS POSSIBILITIES IN THE IM- 
PROVEMENT or PLANTS .... 259 
PIECING THE FRAGMENTS OF A MOTION- 
PICTURE FILM 279 

THE SHASTA DAISY 299 

THE WHITE BLACKBERRY 325 



A WORD TO THE 
READER 

THERE are two classes of mind, 
which, when earnestly employed, 
are rarely combined in the same 
person; the investigator and the re- 
corder,, and when so combined, time 
becomes the one element lacking. The 
investigator and the experimenter who 
is seeking practical results which shall 
be of lasting benefit to the race, cannot 
keep verbose records. He must be on 
the alert in seeking the shortest and 
best methods which shall lead to the 
results sought. 

These eight volumes are not a com- 
pilation from the works or words of 
others, but a description of some of the 

17 



18 LUTHER BURBANK 

results of actual work for the past fifty 
years among millions of living plants, 
including almost every one known to 
growers and many thousand species 
never seen in cultivation, which have 
been discovered by hundreds of my col- 
lectors of seeds of wild plants from 
every part of the earth, most of whom 
(strangers to me) have sent these seeds 
in gratitude for the work accomplished 
here, or in exchange for seeds of my 
improved plants for the various climates 
from which the wild seeds came. 

All these thousands of varieties are 
grown and most carefully inspected and 
selections made for any promise they 
may give of use for fruit or other food, 
for flowers, foliage, lumber, fiber, ex- 
tracts, perfumes or other chemicals, and 
for combination with our well-known 
cultivated trees, plants, and flowers, for 
their improvement. 



A WORD TO THE READER 19 

There is a great amount of litera- 
ture on the subjects treated in these 
volumes, and I have a library of more 
than a thousand books on this and kin- 
dred subjects, most of them being 
theoretical only, or compilations rather 
than records of "actual experimental 
work. 

This work, if carried on extensively, 
requires constant daily and hourly at- 
tention, and these volumes have been 
mostly written on paper pads during the 
occasional wakeful hours of night, with- 
out light, and of course without use of 
my eyes, which have always been too 
much occupied with experiments while 
daylight lasted. Notwithstanding the 
fact that those who are making history 
seldom have time to record it, these 
records have been made for the benefit 
of those who follow, and it is hoped that 
this partial description of actual, vital, 



20 LUTHER BURBANK 

important, productive, and successful 
work may prove of unusual value to 
those who have not had any similar 
fortunate experience, but would be 
guided in the road to success. 

LUTHER BURBANK. 



Santa Rosa, California 
July 1, 1920 



PREFATORY NOTE 

ETHER BURBANK, botanist, nat- 
uralist, and plant breeder, son of 
Samuel W. and Olive (Ross) 
Burbank, was born in Lancaster, Wor- 
cester County, Massachusetts, on March 
7, 1849. His ancestry was English- 
Scotch, the main element being derived 
from the Puritans who followed the 
Mayflower Pilgrims from 1625 to 1640. 
He was educated in the common schools 
and in a local academy. After a short 
experience in an agricultural implement 
manufactory he began market gardening 
and seed growing in a small way, one of 
his first and therefore now best known 
achievements being the development 

of the Burbank potato from a selected 

21 



22 LUTHER BURBANK 

seedling of the Early Rose. On October 
1, 1875, he removed from Massachusetts 
to Santa Rosa, California, where he has 
lived ever since, devoting himself to the 
production of new forms of plants by 
crossing and selection. He is a member 
of various learned societies and for some 
years was lecturer on plant evolution at 
Stanford University. 

Personally Burbank is of medium stat- 
ure, clear-cut in feature and wiry in 
physique, a modest, devoted man of 
science with a keen eye, a deft hand, a 
broad intelligence, and a sensitive soul. 
For half a century he has applied him- 
self whole-heartedly to the work of plant 
improvement. His industry is amazing 
and almost without parallel; through all 
these years he has kept thousands of 
varied experiments going with the math- 
ematical certainty that in the many 
products of his efforts there would 



PREFATORY NOTE 23 

be some new forms of unusual value. 
The few gains are positive acquisition. 
For the sake of one great advance, 
he can afford to burn thousands of 
plants of which the combinations of 
inheritable character show little or no 
improvement over the parent stocks. 

With both animals and plants the 
general process of creating new forms 
must of necessity pass through four 
stages : 

1. Unconscious selection with more or 
less isolation of domesticated forms. 

2. Conscious selection of desirable in- 
dividuals. By this means, those most 
available for man's purposes were pre- 
served, and their traits, differing in 
different regions, became distinctive 
breed characters. This was the method 
by which man created his primitive 
sheep and the wolves he trained (as dogs) 
to guard them. 



24 LUTHER BURBANK 

3. Conscious selection toward definite 
ends. In this way are formed superior 
strains within the various species of 
animals or plants. 

4. Crossing between varieties, races, or 
species to increase range of divergence, 
to add or combine desirable traits, or to 
eliminate others which may be objec- 
tionable. This must be accompanied by 
isolation to prevent panmixia or promis- 
cuous breeding, and also by rigid selec- 
tion directed to a predetermined definite 
end. Such a series of processes makes 
breeding a fine art, one yet in its infancy, 
no doubt, but in its possibilities the 
noblest of all arts. 

No breeder has any patent on his 
methods. These are open as the day to 
all the world and success depends not on 
tricks but on the brains and skill put 
into the work. Since the dawn of civili- 
zation thousands of men have used these 



PREFATORY XOTE 25 

methods, each in his degree, and thou- 
sands will use them again. 

Burbank is proud to acknowledge that 
his success rests on the science of 
Darwin, who first clarified the laws on 
which plant breeding must rest. Science 
is human experience tested and set in 
order; Darwin brought order into the 
confused and contradictory observations 
of thousands of his predecessors. He saw 
the millions of kinds of living things, not 
as disconnected entities resulting from 
specific acts of creation,, but as diverg- 
ing twigs from the great parent tree 
of life. 

The attempt to trace the origin of any 
species leads one back to the two inter- 
nal factors, heredity and variation, each 
in turn checked by external limitations 
of environment which produce selection 
and segregation. Of the multitudes of 
races which spring like suckers from a 



26 LUTHER BURBANK 

vigorous root only those have survived 
which mastered their surroundings. 
Adaptations are perpetuated through the 
nonsurvival of those who failed in ad- 
justment, and separate races are fixed by 
the natural setting apart through isola- 
tion of groups of individuals diverging 
from the parent form. 

All these slow processes of nature can be 
accelerated almost indefinitely through 
a sympathetic knowledge of plant life in 
general, and the wise application of this 
knowledge to the attainment of the spe- 
cial results desired. The experimenter 
creates his own environment, selecting 
those individuals which conform, and 
destroying the others. He then segre- 
gates the chosen ones, that their qualities 
may not be lost in breeding with the 
mass. The law of heredity, "like pro- 
duces like," is interwoven inextricably 
with the law of variation by which no 



PREFATORY XOTE 27 

two organisms, not even two germ cells, 
are ever quite alike. 

Modern studies have given a new 
meaning to the word ancestor, the bearer 
of potentialities, and each new individual 
is a complex of potentialities drawn 
from different sources. Thus, by selection 
and consolidation of successful variants, 
accompanied by separation from the 
mass, most of the species or kinds of 
animals and plants we find in nature 
have been produced. 

"Nature," says Burbank, "has time 
without limit, but man has immediate 
need for better and still better food, 
houses and clothing, and our present 
state of civilization depends largely upon 
the improvements of plants and animals 
which have consciously and half-con- 
sciously been made by man, and future 
civilization must more and more depend 
upon scientific efforts to this end." 



28 LUTHER BURBANK 

By grasping the ways of nature man 
can plan the end from the beginning. 
He may and does create species by using 
nature's methods. Burbank is therefore 
a * 'creator"; so is any other man who 
applies scientific research to the molding 
of life. 

Burbank's experimental gardens at 
Santa Rosa and on the near-by farm at 
Sebastopol may be viewed by the biolo- 
gist as a great laboratory constantly 
yielding valuable data. Though his im- 
mediate purpose is to produce new and 
improved plants for the benefit of 
humanity, it is evident that in so doing 
he works on the borderland of what 
Darwin called "the problem of problems, 
the origin of species.' 5 

Burbank's ways, then, are nature's 
ways, in which success comes to the man 
who follows them most closely. The 
factors which have made him "dean of 



PREFATORY NOTE 29 

plant breeders" are the great range of 
his efforts, the extent of his experiments, 
his keenness in perceiving slight varia- 
tions and their meaning, and the rapidity 
with which he brings results to light by 
the grafting of seedlings on mature 
stocks. Dr. Vernon Kellogg* has well 
said that "the final and most important 
factor of Burbank's success is the inher- 
ent personal genius of the man, his in- 
nate sympathy with nature, aided by 
the practical education in plant biology 
derived from thirty years of constant 
study and experiment which enable him 
to perceive correlations and outcomes of 
plant growth which seem to have been 
visible to no other man." 

I have called Burbank a botanist be- 
cause he is one in the highest, the 
original meaning of the word. But 
Botany with all her sister sciences has 

Scientific Aspects of Luther Burbank's Works. Popular Science 
Monthly, October, 1906. 



30 LUTHER BURBAJXTK 

now spread out into a vast realm far too 
broad for any one man to explore in a 
lifetime. Burbank's special field is that 
of plant genetics; here he is artist as well 
as scientist. Academic, no but science 
is not necessarily bred in the academy. 
Until within the last half century uni- 
versities fought shy of it, regarding exact 
knowledge as "materialistic" or even 
"heretical/ 3 Burbank is not a physiol- 
ogist, still less histologist, and the phe- 
nomena of the physical basis of heredity, 
cell division and cell multiplication, so 
illumined during the last thirty years, 
he has not studied in the universities, 
though his large library contains most 
of the books which relate to these sub- 
jects. In the inheritance of the influ- 
ence of all environment he shows a faith 
most botanists of the day have hesitated 
to share. The extended acceptance of 
Mendelism and mutation as final words 



PREFATORY NOTE 31 

in species making he very definitely 
questions. In the application of a knowl- 
edge of heredity to the art to which it 
gives rise in the plant world his suprem- 
acy is unchallenged. 

I quote again from Burbank: "A 
knowledge of Mendelism is recognized 
by me as only the A B C to the broader 
knowledge of heredity necessary for 
success in animal and plant improve- 
ment, and all variations and all muta- 
tions of every nature are responses to 
environment which, by repetition and 
combination, are slowly but surely fixed 
in heredity and at last made tangible, 
most often through the crossing of 
varieties, species, or genera, either by 
nature or that part of nature called 



man.' 



Among other things Burbank has 
shown that while "sex is not a necessary 
attribute of all living things," it is "a 



32 LUTHER BURBANK 

most necessary attribute if progress in 
evolution of new forms is to occur, as 
they have progressed through the ages 
and as we now see them progressing on 
this planet." Furthermore, he has in- 
sisted that the ' 'power to vary in plants 
or animals is itself a feature as readily 
transmissible as is stability of character. 
The quality of varying to meet varying 
environments is therefore one of the 
hereditary traits which the plant breeder 
must consider, and which may itself be 
extended or overcome by the processes 
of crossing and selection 

"It is increasingly necessary (he says) 
to impress the fact that there are two 
distinct lines in the improvement of any 
race: the environment which brings indi- 
viduals up to their best possibilities; the 
other, ten thousand times more impor- 
tant and effective, selection of the best 
individuals through a series of genera- 

Vol. 1 Bur. A 



PREFATORY NOTE 33 

tions. ' ' These two lines correspond re- 
spectively to Galton's two elements in 
individual development, " Nurture" and 
"Nature." 

Burbank worked for years alone, not 
understood nor appreciated, and usually 
at a financial loss, for his instincts and 
aims were those of a scientist, not of a hor- 
ticulturist. To have tried fewer experi- 
ments, and those only along lines likely 
to prove commercially valuable, would 
have brought him money but not satis- 
faction. In his way, he belongs to the 
class of Faraday and the self-taught men 
of the last generation who dealt steadily 
with facts, while universities spent their 
energies on fine points of grammar, and 
a philosophy which, like an epiphytic 
plant, had its roots in the air. 

My own first realization of Burbank's 
scientific eminence came from Dr. Hugo 
de Vries, botanist of the University of 



Vol. 1 Bur. B 



34 LUTHER BURBANK 

Amsterdam, who, at a dinner in San 
Francisco in 1904, spoke the following 
words of eulogy: 

66 A unique, great genius! To see him 
was the prime reason of my coming to 
America. He works to definite ends. 
He ought to be not only cherished but 
helped. Unaided he cannot do his 
best. He should be as well known and 
as widely appreciated in California as 
among scientific men in Europe." 

Scientists are of many types. Some 
observe, some compare, some experi- 
ment, some deal with general principles, 
and others carry over knowledge into 
action. There is need for all kinds and 
a place for all. With broader oppor- 
tunities, Burbank could have done a 
greater variety of things and touched life 
at more points ; but he would thus have 
lost something of his simple intensity 
and fine delicacy things the schools do 



PREFATORY NOTE S.5 

not give and too much contact with 
society sometimes takes away. 

Big men are usually of simple, direct 
sincerity of character. These marks are 
found in Burbank, sweet, straightfor- 
ward, unspoiled as a child, devoted to 
truth, never turning aside to seek fame 
or money or other personal reward. If 
his place be outside the great temple of 
science, not many of the rest of us will 
be found fit to enter. 

DAVID STARR JORDAN. 



Stanford University, California 
July 5, 1921 



FUNDAMENTAL PRINCIPLES 
OF PLANT BREEDING 

ONLY the most limited view of plant 
breeding can be given in a chapter of 
ordinary length. It would be necessary 
to extend the subject through many volumes 
to give even a general view of what has already 
been demonstrated, and that which the clear 
light of science has yet to bring forth from the 
depths is too extensive even for the imagination 
to grasp, even through a full knowledge of what 
practical field work has already accomplished. 

The fundamental principles of plant breeding 
are simple, and may be stated in few words ; the 
practical application of these principles demands 
the highest and most refined efforts of which the 
mind of man is capable, and no line of mental 
effort promises more for the elevation, advance- 
ment, prosperity, and happiness of the whole 
human race. 

Every plant, animal, and planet occupies its 
place in the order of nature by the action of 
two forces the inherent constitutional life force 

37 



38 LUTHER BURBANK 

with all its acquired habits, the sum of which is 
heredity; and the numerous complicated exter- 
nal forces, or environment. To guide the inter- 
action of these two forces, both of which are 
only different expressions of the one eternal 
force, is, and must be, the sole object of the 
breeder, whether of plants or animals. 

When we look about us on the plants inhabit- 
ing the earth with ourselves and watch any 
species day by day, or year by year, we are 
unable to see any change in some of them. Dur- 
ing a lifetime, and in some cases, perhaps, in- 
cluding the full breadth of human history, no 
remarkable change seems to have occurred. And 
yet there are to-day few, if any, plant species 
which have not undergone great, and to a certain 
extent are undergoing, constant change the 
invisible changes often appearing abruptly with- 
out apparent cause. 

The life forces of the plant, in endeavoring 
to harmonize and adapt the action of its acquired 
tendencies to its surroundings, may, through 
many generations, slowly adapt itself to the 
necessities of existence, yet these same accrued 
forces may also produce sudden, and to one not 
acquainted with its past history, most surprising 
and unaccountable, changes of character. The 
very existence of the higher orders of plants 



PLANT BREEDING 39 

which now inhabit the earth has been secured 
to them only by their power of adaptation to 
crossings, for, through the variations produced 
by the combination of numerous tendencies, 
individuals are produced which are better en- 
dowed to meet the prevailing conditions of life. 
Thus to nature's persistence in crossing do we 
owe all that earth now produces in man, animals, 
or plants; and this magnificently stupendous 
fact may also be safely carried into the domain 
of chemistry as well, for what is common air and 
water but nature's earlier efforts in that line, 
and our nourishing foods but the result of 
myriad complex chemical affinities of later date? 
Natural and artificial crossing and hybridiza 
tion are without doubt among the principal 
remote causes of nearly all otherwise perplexing 
or unaccountable sports and strange modifica- 
tions, and also of many of the now well-estab- 
lished species. Variations, without immediate 
antecedent crossing, occur always and every- 
where from a combination of past crossings and 
environments, for potential adaptations often 
exist through generations without becoming 
actual, and when we fully grasp these facts there 
is nothing so very mysterious in the sudden 
appearance of sports ; but still further intelligent 
crossing produces more immediate results and of 



A CROSS OF ORANGE AND 
LEMON 

These curious citrus fruits, which 
occur spontaneously from time to time, 
do not appear from immediate crossing 
of the varieties, but from latent ten- 
dencies which appear from former 
crossings. 



PLANT BREEDING 41 

great value, not to the plant in its struggle with 
the ordinary natural forces, but to man, by con- 
serving and guiding its life forces to supply him 
with food, clothing, and innumerable other 
luxuries and necessities. Plant life is so com- 
mon that one rarely stops to think how utterly 
dependent we are upon the quiet, but magnifi- 
cently powerful work which is being constantly 
performed for us. 

It was once thought that plants varied within 
the so-called species but very little, and that true 
species never varied. We have more lately dis- 
covered that no two plants are ever exactly alike, 
each one having its own individuality, and that 
new varieties having endowments of priceless 
value, and even distinct new fixed botanical 
species can be produced by the plant breeder, 
often with almost the same precision that ma- 
chinery for locomotion and other useful purposes 
are produced by the mechanic. 

The evolution and variation of plants are 
simply the means which they employ, as species, 
in adjusting themselves to external conditions. 
Each plant must adapt itself to environment 
with as little demand upon its forces as possible 
and still keep up in the race. The best endowed 
species and individuals win the prize, and by 
variation as well as persistence. The constantly 



42 LUTHER BURBANK 

varying external forces to which all life is every- 
where subjected demand that the inherent inter- 
nal force shall always be ready to adapt itself 
or perish. 

The combination and interaction of the innu- 
merable forces embraced in heredity and environ- 
ment have given us all our bewildering species 
and varieties, none of which ever did or ever will 
remain always constant, for the inherent life 
force must be pliable, or outside forces will 
sooner or later extinguish it. Thus adaptability, 
as well as perseverance, is one of the prime 
virtues in plant as in human life. 

Plant breeding is the intelligent application 
of the forces of the human mind in guiding the 
inherent life forces into useful directions by 
crossing to make perturbations or variations and 
new combinations of these forces, and sometimes 
by radically changing environments, both of 
which produce somewhat similar results, thus 
giving a broader field for selection, which again 
is simply the persistent application of mental 
force to guide and fix the perturbed life forces 
in the desired new channels. 

Plant breeding is in its earliest infancy. Its 
possibilities, and even its fundamental principles, 
are understood but by few; in the past it has 
been mostly dabbling with tremendous forces, 



PLANT BREEDING 43 

which have been only partially appreciated, and 
it has yet to approach the precision which we 
expect in the handling of steam or electricity, 
and, notwithstanding the occasional sneers of the 
ignorant, these silent forces embodied in plant 
life have yet a part to play in the regeneration 
of the race which by comparison will dwarf into 
insignificance the services which steam and elec- 
tricity have so far given. Even unconscious or 
half-conscious plant breeding has been one of 
the principal forces in the elevation of the race. 
The chemist and the mechanic have, so to speak, 
domesticated some of the forces of nature, but 
the plant breeder is now learning to guide even 
the creative forces into new and useful channels. 
This knowledge is a most priceless legacy, mak- 
ing clear the way for some of the greatest bene- 
fits which man has ever received from any source 
by the study of nature. 

A general knowledge of the relations and 
affinities of plants will not be a sufficient equip- 
ment for the successful plant breeder. He must 
be a skillful botanist and biologist, and, having a 
definite plan, must be able to correctly estimate 
the action of the two fundamental forces, inher- 
ent and external, which he would guide. 

The main object of crossing genera, species, 
or varieties is to combine various individual ten- 



THORNLESS BLACKBERRY 
BLOSSOMS 

As to its blossom, the Thornless is 
a typical and characteristic blackberry. 
The smooth stem may make one doubt., 
but on observation of the flower, and 
later, on viewing the great abundance 
of its sweet, luscious fruit, its unusual 
value is very fully appreciated. 



PLANT BREEDING 45 

dencies, thus producing a state of perturbation 
or partial antagonism by which these tendencies 
are, in later generations, dissociated and recom- 
bined in new proportions, which gives the breeder 
a wider field for selection ; but this opens a much 
more difficult one the selection and fixing of 
the desired new types from the mass of hetero- 
geneous tendencies produced, for, by crossing, 
bad traits as well as good are always brought 
forth. The results now secured by the breeder 
w T ill be in proportion to the accuracy and inten- 
sity of selection and the length of time they are 
applied. By these means the best of fruits, 
grains, nuts, and flowers are capable of still 
further improvements in ways which to the 
thoughtless often seem unnecessary, irrelevant, 
or impossible. 

When we capture and domesticate the various 
plants, the life forces are relieved from many of 
the hardships of an unprotected wild condition 
and have more leisure, so to speak, or in other 
words, more surplus force, to be guided by the 
hand of man under new environments into all 
the useful and beautiful new forms which are 
constantly appearing under cultivation, crossing, 
and selection. Some plants are very much more 
pliable than others, as the breeder soon learns. 
Plants having numerous representatives in 



46 LUTHER BURBANK 

various parts of the earth generally possess this 
adaptability in a much higher degree than the 
monotypic species, for, having been subjected to 
great variations of soil, climate, and other in- 
fluences, their continued existence has been 
secured only by the inherent habits which adap- 
tation demanded, while the monotypic species, 
not being able to fit themselves for their sur- 
roundings without a too radically expensive 
change, have continued to exist only under cer- 
tain special conditions. Thus two important 
advantages are secured to the breeder who selects 
from the genera having numerous species the 
advantage of natural pliability, and in the nu- 
merous species to work upon by combination for 
still further variations. 

Before making combinations we should, with 
great care, select the individual plants which 
seem best adapted to our purpose, as by this 
course many years of experiment and much 
needless expense will be avoided. The differences 
in the individuals which we have to work upon 
are sometimes extremely slight. The ordinary 
unpracticed person cannot by any possibility 
discover the exceedingly minute variations in 
form, size, color, fragrance, precocity, and a 
thousand other characters which the practiced 
breeder perceives by a lightninglike glance. 



PLANT BREEDING 47 

The work is not easy, requiring an exceedingly 
keen perception of minute differences, great 
accuracy, and extreme care in treating the or- 
ganisms operated upon, and even with all the 
inherent naturally acquired variations added to 
those secured by scientific crossing and numerous 
other means, the careful accumulation of slight 
individual differences through many generations 
is imperative, after which several generations 
are often, but not always, necessary to thor- 
oughly "fix" the desired type for all practical 
purposes. 

The above applies to annuals, or those plants 
generally reproduced by seed each season. The 
breeder of plants which can be reproduced by 
division has great advantage, for any valuable 
individual variation can be multiplied to any 
extent desired without the extreme care neces- 
sary in fixing by linear breeding the one which 
must be reproduced by seed. But even in breed- 
ing perennials the first deviations from the ori- 
ginal form are often almost unappreciable to the 
perception, but by accumulating the most minute 
differences through many generations the devia- 
tion from the original form is often astounding. 
Thus, by careful and intelligent breeding any 
valued quality may be made permanent, and 
valid new species are at times produced by the 



48 LUTHER BURBANK 

art of the breeder, and there is no known limit 
to the improvement of plants by education, 
breeding, and selection. 

The plant breeder is an explorer into the in- 
finite. He will have "No time to make money," 
and his castle, the brain, must be clear and alert 
in throwing aside fossil ideas and rapidly replac- 
ing them with living, throbbing thought, followed 
by action. Then, and not till then, shall he 
create marvels of beauty and value in new ex- 
pressions of materialized force, for everything of 
value must be produced by the intelligent appli- 
cation of the forces of nature which are always 
awaiting our commands. 

The vast possibilities of plant breeding can 
hardly be estimated. It would not be difficult 
for one man to breed a new rye, wheat, barley, 
oat, and rice which would produce one grain 
more to each head, or a corn which would pro- 
duce an extra kernel to each ear, another potato 
to each plant, or an apple, plum, orange, or nut 
to each tree. 

What would be the result? In five staples 
only, in the United States alone, the inexhaust- 
ible forces of nature would produce annually, 
without effort and without cost, 6,000,000 
extra bushels of corn, 15,300,000 extra bushels 
of wheat, 42,000,000 extra bushels of oats, 



PLANT BREEDING 49 

2,100,000 extra bushels of barley, 24,000,000 
bushels of potatoes. 

But these vast possibilities are not alone for 
one year, or for our own time or race, but are 
beneficent legacies for every man, woman, and 
child who shall ever inhabit the earth. And who 
can estimate the elevating and refining influences 
and moral value of flowers with all their graceful 
forms and bewitching shades and combinations 
of colors and exquisitely varied perfumes? 
These silent influences are unconsciously felt 
even by those who do not appreciate them con- 
sciously, and thus with better and still better 
fruits, nuts, grains, and flowers will the earth 
be transformed, man's thoughts turned from the 
base, destructive forces into the nobler produc- 
tive ones which will lift him to higher planes 
of action toward that happy day when man 
shall offer his brother man, not bullets and 
bayonets, but richer grains, better fruits, and 
fairer flowers. 

Cultivation and care may help plants to do 
better work temporarily, but by selective breed- 
ing plants may be brought into existence which 
will do better work always in all places and for 
all time. Plants are to be produced which will 
perform their appointed work better, quicker, 
and with the utmost precision. 



A LARGE, LATE-BEARING RED 
SEEDLING CHERRY 

The cherry here shown (enlarged 
one-eighth), developed in our colony, 
differs from the one specifically called 
the "Burbank" in that it is a very late 
bearer. The "Burbank" bears particu- 
larly early in the season. It is desirable 
to extend the cherry season, and this 
variety has been preserved chiefly be- 
cause of its lateness, although it has 
many other desirable qualities, as the 
picture suggests. 



PLANT BREEDING 51 

Science sees better grains, nuts, fruits, and 
vegetables all in new forms, sizes, colors, and 
flavors, with more nutrients and less waste, and 
with every injurious and poisonous quality elim- 
inated, and with power to resist sun, wind, rain, 
frost, and destructive fungus and insect pests; 
fruits without stones, seeds, or spines; better 
fiber, coffee, tea, spice, rubber, oil, paper and tim- 
ber trees, and sugar, starch, color, and perfume 
plants. Every one of these, and ten thousand 
more, are within the reach of the most ordinary 
skill in plant breeding. 

On scientific plant development now rests one 
of the next great world movements; the guid- 
ance of the creative forces are in our hands. 

Man is slowly learning that he, too, may guide 
the same forces which have been through all the 
ages performing this beneficent work which he 
sees everywhere above, beneath, and around him 
in the vast teeming animal and plant life of the 
world. 

These lines were penned among the heights 
of the Sierras, while resting on the original 
foundation material from which this planet was 
made. Thousands of ages have passed, and it 
still remains unchanged. In it no fossils or any 
trace of past organic life are ever found, nor 
could any exist, for the world-creative heat was 



52 LUTHER BURBANK 

too intense. Among these dizzy heights of rock, 
ice-cleft, glacier-plowed, and water-worn, we 
stand face to face with the first and latest pages 
of world creation, for now we see also tender 
and beautiful flowers adding grace of form and 
color to the grisly walls, and far away down the 
slopes stand the giant trees, oldest of all living 
things, embracing all of human history ; but even 
their lives are but as a watch tick since the stars 
first shone on these barren rocks, before the evo- 
lutive forces had so gloriously transfigured the 
face of our planet home. 



"Some qualities nature carefully 
fixes and transmits, but some, and 
those the finer, she exhales with the 
breath of the individual as too 
costly to perpetuate. But I notice 
also that they may become fixed 
and permanent in any stock, by 
painting and repainting them on 
every individual, until at last na- 
ture adopts them and bakes them 
into her porcelain" EMERSON. 



EVOLUTION AND VARIATION 

WITH THE FUNDAMENTAL 

SIGNIFICANCE OF SEX 

IN searching for knowledge on any subject, 
it is quite evident that it is best, if possible 

to start with the foundation facts before at- 
tempting to build any useful or beautiful struc- 
ture, and it will be necessary in this case to 
repeat some facts available to specialists, but not 
so generally known or appreciated by others, 
for upon a knowledge of fundamentals depends 
the life of any structure. 

As a specialist in the study of nature for the 
definite purpose of producing new forms of 
plant life, for the better nourishment, housing, 
and clothing of the race, and the creation of new 
fragrances and new shades of color in flowers 
to make life more beautiful, certain very definite 
conclusions regarding life and its origin on this 
and probably on other planets have been im- 
pressed upon me. 

Life is self-expression a challenge to environ- 
ment. It is action in certain definite directions 

53 



54 LUTHER BURBANK 

based on mechanical and chemical change. In 
nature we find varied animate and inanimate 
forms of life, many of which have motions 
some of which in the higher forms we call emo- 
tions. These sometimes end in action, at other 
times in thought. 

By common consent we usually associate life 
as commencing with the unit of life the indi- 
vidual cell but life really exists as an organized 
force in all growing crystals and in a review of 
the fundamentals of life we must go even to a 
more primitive form than that of crystal life; 
below even these we find, instead of the organized 
growth seen in crystals, an amorphous life. The 
substances called colloids have no definite struc- 
ture like crystals, yet they respond to some of 
the same forces which act upon crystals and upon 
individual unit cells. These colloidal substances 
have no very well defined visible structural forms 
like crystals, yet some of the lowest forms 
of animal life, like the amoeba, are almost as 
indefinite in form and structure; in fact, having 
no more definite form than a piece of soft putty 
or a passing cloud; just a mass of jelly, yet able 
to perform all the functions and motions neces- 
sary to animal life in its primitive state. 

Both crystals, the amoeba and other unicellular 
forms, respond definitely to some of the forces 



EVOLUTION AND VARIATION 55 

of nature, such as gravity, heat, and light; in 
other words, have the quality of positive and 
negative reactions a limited power of choice; 
and from such faint prophecies of life, just 
emerging from the realm of chemistry, have 
come during aeons of time all the varied plant 
and animal life on this earth, including man 
himself. 

In a review of the fundamentals of life, we 
may fairly commence with the crystal forms. 
Crystals grow when surrounded by a solution 
which contains abundant nourishment in a tem- 
perature adapted to the species, but from the 
outside, very much like plants and trees in which 
the nourishing leaf-digested protoplasmic sap 
flows down, usually in the cambium between the 
bark and wood, adding thin layers of growth 
very much after the manner of silver plating, or 
sedimentation in muddy water. 

Crystals, like plants and animals, grow into 
certain specific forms which may vary to a cer- 
tain extent to accommodate themselves to their 
environment, for heredity and environment must 
be reasonably well fitted to each other, or life 
always ceases to exist. The internal heredity 
(formerly acquired) forces and the external or 
environmental forces must be adapted to meet 
each other somewhat as a garment fits the body, 



56 LUTHER BURBANK 

not exactly but approximately, and the better 
the fit the more harmonious the conditions 
within. 

Crystals, like mushrooms, may live and grow 
without the direct influence of light, while most 
plants depend wholly upon the action of light 
for life, and all animal life depends absolutely 
and wholly for all its nourishment upon the 
action of sunlight upon the foliage of plants. 
All food comes first from foliage. The sun feeds 
the earth from its abundance and by it life is 
awakened and sustained. 

Unicellular plant life was, without any possible 
doubt, the first form of primitive living organism 
which appeared on this planet. A cell is an 
individual entity developed by its environment 
from more or less amorphous colloidal sub- 
stances. It is plain that to exist and have an 
individuality it must be separated from the rest 
of the cosmos. A cell is, in short, a package of 
protoplasmic substance inclosed from the rest of 
the cosmos in its protective covering, large or 
small, usually very small. Protoplasm, the base 
of all plant and animal life, is an amorphous 
compound composed of various chemical sub- 
stances in a very complicated and unstable form, 
as is always the case with all vegetable and ani- 
mal nourishing foods; in other words, it is an 



EVOLUTION AND VARIATION 57 

existence separated from the rest of the cosmos, 
with possibilities of change, for life does not 
exist except through change; it is always chang- 
ing, never static, though it sometimes appears tc 
be so in the resting stage, as in seeds, eggs, and 
the hibernating state of plants, animals, and crys- 
tals, all of which appear to be absolutely dead 
and as lifeless as a brick; but furnish them with 
their proper nourishing food, in a liquid form 
with a temperature adapted to the heredity of 
the species, and observe how quickly they resume 
growth, even crystals, like plants, under the 
proper environment, moving out of the resting 
or dormant stage into the full manifestation of 
all their attributes. 

The cell, being a protoplasmic substance in an 
envelope an individual mass of more or less 
complicated chemical substances in a very un- 
stable condition, separated from the rest of the 
cosmos surrounding it by a case or wall has 
made the first step toward a more complete life. 
Until such separation, there is little opportunity 
for any permanent individual change or evolu- 
tion to occur. 

The protoplasm of the amrebic forms of life 
is compelled to lead a very uncertain existence; 
the better conservation of life must come from 
a fuller individuality. This is assured by a skin 



58 LUTHER BURBANK 

of protective envelope separating the individual 
from the rest of the cosmos, so that it can enjoy 
individual life and in no other way could this 
permanently be secured. Even chemicals do not 
retain their individual character unless inclosed 
in packages or bottles or cells of some kind, 
so the cell is a unit of all individual life and it is 
very evidently necessarily so, in order to meet 
the obstacles to full development under oppos- 
ing environment, but it is plain that environ- 
mental obstacles can be more readily overcome 
by a combination of cells. Of course these cell 
colonies would, in the very nature of the circum- 
stances, be better adapted to survive than single 
individuals; thus colonies must very naturally 
have arisen by accretion, producing, during the 
lapse of ages, all the various forms of vegetable 
and animal life which the conditions on our 
planet have now brought and are yet bringing 
forth. Cell colonies must preserve their very 
existence by adapting themselves to the aid of 
all other members of the cell colony therefore 
must become specialists in certain directions; 
thus seed, bark, wood, and leaf cells in plants; 
and blood, liver, brain, bone, and muscle cells 
in animal life, though retaining their individu- 
ality as modified cells, yet have become, by stress 
of environment, specialists, for by specialization 



EVOLUTION AND VARIATION 59 

only can the functions of a colony be maintained, 
and upon its integrity depends its continued 
existence; it must depend upon specialized 
individuals. 

As in multicellular life, so in the structure of our 
human social fabric individual human life must 
be specialized to a certain extent so that we may 
adapt ourselves to existence with one another. 
Individuals cannot exist except through the mu- 
tual aid of one another. The same laws govern 
cell life, human life, all life. These fundamental 
laws cannot be evaded. They apply to personal, 
social, and national life, and any virtue or defect 
in an individual infallibly affects the whole. 

It has been said that a "House divided against 
itself must fall." A plant, an animal, a man, 
a society, a nation, a continent or a world 
whose individual units do not cooperate har- 
moniously is on the highroad to destruction. 
All that is precious to the whole human race 
is devastated by war which threatens to de- 
stroy from the earth much that had been built up 
faithfully and painfully during centuries for the 
best interests of the race. 

THE FUNDAMENTAL SIGNIFICANCE OF SEX 

We find these words in a late scientific work 
by Dr. L. Doncaster, Fellow of King's College, 



50 LUTHER BURBANK 

Cambridge, England; published by the Univer- 
sity Press : 

It is a remarkable thing that apart from the funda- 
mental attributes of living matter assimilation, irritability, 
growth, and so forth no single character is so widely dis- 
tributed as sex ; it occurs in some form in every large group 
of plants and animals from the highest to the lowest and 
yet of its true nature and meaning we have hardly a sus- 
picion. Other widely distributed characters have obvious 
functions; of the real function of sex we know nothing, 
and in rare cases where it seems to have disappeared, the 
organism thrives to all appearances just as well without 
it. And in many other cases, especially in plants, where 
sex is definitely present, it may apparently be almost or 
quite functionless, as for example, in the considerable num- 
ber of plants which are habitually grown from grafts or 
cuttings, and in which the fertile seeds are never set. It 
is of course impossible to say with confidence that such 
"asexual" reproduction can go on quite indefinitely, but the 
evidence formerly adduced that continued vegetative repro- 
duction leads to degeneration has been shown to be of 
doubtful validity. Sex, therefore, although it is almost 
universally found, cannot be said with certainty to be a 
necessary attribute of living things, and its real nature re- 
mains an apparently impenetrable mystery. 

Now, after more than fifty years of practical 
experiments in the evolution of new plant forms, 
the purpose of sex seems too plain even to need 
much explanation, much less any doubt what- 
ever as to its purpose in the scheme of things. 



EVOLUTION AND VARIATION 61 

Sex is not a necessary attribute of living things, 
but it is a very necessary attribute if progress in 
the evolution of new forms is to occur, as they 
have progressed through the past ages and as we 
now see them progressing on this planet. 

We have lately learned that the power to vary 
in plants and animals is as readily transmissible 
as stability of character and we also now know 
that plants and animals brought up for genera- 
tions under different environments acquire dif- 
ferent habits and appearances and, after a 
time, differences in structure. Each species 
has had different experiences in adapting itself 
to its surroundings, and no two individuals 
of any species, though having similar experi- 
ences, have exactly the same. By combination 
the experiences of both are, by heredity, trans- 
mitted either latently or obviously to one or 
many of their descendants. This combination 
by crossing, happening again and again, gives 
added ability to meet and overcome every chang- 
ing environment; in other words, the power to 
vary to meet varying environment, and by addi- 
tion fixing characters which benefit the species 
through natural selection, giving the new com- 
binations new abilities to advance. Only thus, 
through combination by sex, has the marvelous 
variety of plants and animals which now have 



ORDINARY FIELD CORN AND 
ITS TINY PARENT 

In the direct-color photograph print 
shown here a typical ear of "dent" corn 
is placed for comparison beside the tiny, 
half wild, teosinte ear which the pre- 
historic Indians discovered and im- 
proved. 



EVOLUTION AND VARIATION 63 

a home on this planet, been brought into 
existence. 

The first primitive chemosynthetic half-plant, 
half-animal life forms without doubt commenced 
self-expression in and near water, as we also now 
find them. These lower forms most often multi- 
ply by spontaneous breaking to pieces by fission 
or simple division, and many plants and some 
animals even, which belong to the higher orders, 
still retain this power to a certain extent, but 
no race of either plants or animals ever made 
any great evolutionary advances until they had 
adopted a better, more specialized and more 
economical means. The most ancient races of 
these early forms very closely resembled those 
now in existence. 

The primitive plan of self-division into equal 
or many parts, when replaced by the more eco- 
nomical and far more effective one of specialized 
cells to accomplish the same purpose, also made 
possible the great variety of life which now exists 
before us. The change from the old to the new 
plan was not immediately adopted by all life by 
any means. Ages passed before the liverworts 
and ferns appeared, which are among the earlier 
forms of true plant life. These bear no real 
seeds, and the specialized cells are dependent 
upon rains or other moving water to carry them 



64 LUTHER BURBANK 

to unite with others to effect a combination of 
their heredities. Variation must have been almost 
inconceivably slow before this era of more eco- 
nomical combinations of hereditary acquirements 
occurred. It is progressing to-day more rapidly 
than ever since plants and animals appeared on 
the earth. New varieties, new species, and new 
genera are all now being produced more rapidly 
than ever since the sun first gave light to the 
planet. 

The pines and similar plants were developed 
later. These had employed another great up- 
ward step, employing the wind to carry the pre- 
cious package of heredity to another. Most of 
the forest trees are of this class ; they do not vary 
as do most other flowering trees and plants. 

The next step in advance in this direction was 
when insects arrived and by cooperation began 
carrying the heredity packages of pollen from 
place to place, for which they received in return 
a taste of honey. Now comes an era of most 
astounding development. More than a hundred 
and forty thousand species were brought into 
existence and most annual plants and many 
trees and shrubs and herbs now began, through 
the selective influence of insects, to produce more 
conspicuous and fragrant flowers and to secrett 
honey just in the exact position to induce insects 



EVOLUTION AND VARIATION 65 

to search for it, and, in so doing, transfer hered- 
ity. No tree or plant that depends permanently 
and wholly on water or wind to carry heredity 
has bright colors, fragrance, or a secretion of 
honey, while all which do depend upon them 
have one or all of these for inducement to the 
insects. Besides all this, each species is adapted 
to visits of certain insects, and most often to pre- 
vent others. The most wonderful and varied 
structures in nature are here to be seen. Is this 
for no purpose or for an unseen one? No! From 
this fact of sex and through its action in com- 
bining heredity acquirements, causing infinitely 
complex combinations, the evolution into a world 
of a million varied forms has been accomplished. 
Then why ask the purpose of sex? Is it not self- 
evident, or why call it an impenetrable mystery? 

After having discussed the most vital aspects 
of the matter, we may now proceed to some very 
definite conclusions. 

Abundant, well-balanced nourishment and 
thorough culture of plants or animals will al- 
ways produce good results in holding any spe- 
cies or variety up to its best heredity possibili- 
ties, beyond which it cannot carry them, and, 
lacking which, maximum development can nevei 
be realized. But a sharp line must always be 
drawn between the transient results temporarily 

Vol. 1 Bur. C 



AN EXPERIMENT IN 
CORN 

The ear of corn shown at the left is 
one which, on an ordinary corn plant, 
was allowed to take its course, except 
that one-third of the silk was cut away, 
leaving a lopsided ear. The other ear 
is one which was covered with a paper 
bag at the time when the pollen was 
falling. The strands of silk thus being 
protected from pollen, the kernels be- 
neath did not mature. It will be seen 
from this that the breezes are as neces- 
sary to the corn plant as the bees and 
birds are to the flowers. 



EVOLUTION AND VARIATION 67 

attained through favorable environment and the 
permanent results of selection of the best indi- 
viduals for continuing the race. 

What would be the result if all apple, plum, 
corn, melon, or petunia seed was indiscriminately 
planted? Soon worthless mongrels only, having 
no character and no value for any purpose. 

Only by constant selection of the best can any 
race ever be improved. No education, no en- 
vironment of any nature can ever make any 
appreciable progress, even though these same 
favorable surroundings may produce through 
ages a definite but infinitely slow increment, 
which by constant repetition becomes slowly 
available in heredity, but through many gener- 
ations by no means fixed, so that reproduc- 
tion true to the better type can be depended 
upon. 

It is becoming increasingly necessary to im- 
press the fact that there are two distinct lines in 
the improvement of any race; one by favorable 
environment which brings individuals up to their 
best possibilities; the other ten thousand times 
more important and effective selection of the 
best individuals through a series of generations. 
By this means, and by crossing, can any race 
of plants, animals, or man be permanently or 
radically improved. 



68 LUTHER BURBANK 

These facts being known, we know how to 
proceed and, difficult as it may appear, it is the 
only route by which any permanent advances 
can, or ever will, be made. When these two 
lines of action are combined, all the best quali- 
ties of any type are brought forth and gradually 
fixed and the field for improvement is limit- 
less. 



HOW PLANTS ADAPT THEM- 
SELVES TO CONDITIONS 

THE INFLUENCE OF ENVIRONMENT 

IT is the two acres of spineless cactus on one 
of my experiment farms which first strikes 
the eye. On the same grounds there are some 
3,000 other experiments under way new flow- 
ers, fruits, vegetables, trees, and plants of all 
descriptions such as man has never before seen, 
but the velvet-leaved cactus freed from its 
thorns seems more than a plant transforma- 
tion; it seems to some a miracle. 

Every native plant growing on the desert is 
either bitter, poisonous, or spiny. It was this 
fact which gave me the suggestion for producing 
this new plant a plant which already has shown 
its ability to outdo alfalfa five to one in quantity 
and which promises to support our cattle on 
much land which has heretofore been considered 
useless, so that our ranges may be turned into 
gardens to produce the vegetable sustenance for 
a multiplying population. 

69 



ARMORED AGAINST ITS 
ENEMIES 

The spines of a cactus are so 
arranged as to protect every inch of 
surface. In addition to the large 
bristling spines which fan out in every 
direction, there is hidden behind each 
rosette a bundle of smaller spines, 
numbering hundreds to each eye. 
When the outward spines are re- 
moved, these push their way forward 
with surprising vigor. The form of 
cactus in the accompanying picture 
illustrates the fact that away back in 
history the cactus may have had round 
stalks instead of flat slabs. 



ENVIRONMENT 71 

Let us look at the life history of the cactus 
as it unfolds itself, realizing the importance of 
the simple fact that desert plants are usually 
bitter, poisonous, or spiny. 

Here are plants which have the hardiness to 
live, and to thrive, and to perpetuate themselves 
under conditions in which other useful plants 
could not thrive. 

Here are plants which, although there may 
not be a drop of rain for a year, two years, or 
even ten, still contrive to get enough moisture 
out of the deep soil and out of the air, to build 
up a structure which, by weight, is 92 per cent 
water plants which contrive to absorb from the 
scorching desert, and to protect from the wither- 
ing sun, enough moisture to make them nearly 
as nutritious as beefsteak, watermelons, or pas- 
ture grasses. 

Here are plants which are veritable wells of 
water, growing in a land where there are no 
springs, or brooks, nor even clouds to encourage 
the hope of a cooling rain; here are plants which 
are rich in nutriment for man and the domestic 
animals; here in the desert where the demand 
for food is most needed and the supply most 
scanty. 

And here they are, ruined for every useful 
purpose to man by the spiny armor which places 



72 LUTHER BURBANK 

their store of nutriment and moisture beyond 
reach. 

There is a reason for these spines. 

What other reason could there be than that 
these are nature's provisions for self-defense? 

Here is the sagebrush, with a bitterness as 
irritant almost as the sting of a bee, the euphor- 
bia as poisonous as a snake, the cactus as well 
armored as a porcupine and for the same rea- 
son that bees have stings, that snakes have fangs 
that porcupines have arrowlike spines for self 
protection from some enemy which seeks tc 
destroy. 

Self-preservation comes before self-sacrifice 
in plant life as it sometimes does in human 
life. 

The apple, cherry, peach, and plum trees in 
our orchards bear luscious fruits in abundance; 
the roses, geraniums, and lilies surrounding our 
dwellings seem to compete to see which may give 
us the greatest delight. 

But is it not because we have selected, fos- 
tered, nurtured, and cared for them? 

Is it not because we have made it easy for 
them to live and to thrive? 

Is it not because we have relieved them of the 
responsibility of defense and reproduction that* 
they have rewarded our kindly care by bloom- 



ENVIRONMENT 73 

ing and fruiting, not for their own selfish ends, 
but for us? 

We do not cherish the wild cactus or the 
poisonous euphorbia. We do not cultivate the 
sagebrush. 

Is it, then, to be wondered at that the primal 
instinct of self-preservation has prevailed that 
what might have been a food plant equal to the 
apple transformed itself into a wild porcupine 
among plants? 

That which might have been as useful to cattle 
as hay changed its nature and became bitter, 
woody, inedible. 

That which might have been a welcome friend 
to the weary desert traveler grew instead into a 
poisonous enemy. 

If the bitterness, the poison, and the spines 
are means of self-defense, then they must be 
means which have been acquired. These plants 
were growing here before their habitation be- 
came so arid, when animals had an abundance 
of other food instead of depending entirely upon 
them; so there must have been a time in their 
history when they had no need for these various 
defenses. 

How, in sixteen years, I have carried the 
cactus back ages in its ancestry, proving satis- 
factorily by planting millions of cactus seeds 



74 LUTHER BURBANK 

that the spiny cactus descended from a smooth- 
slabbed line of forefathers and how these old 
characteristics have been not only reestablished 
but accentuated all of these things will be ex- 
plained in due course where the discoveries in- 
volved and the working methods employed may 
be made applicable as well to the improvement 
of other plants. 

It suffices, here, to say that, beginning with 
this simple observation and reading the history 
of the cactus from its present-day appearance, 
I was able to see outlined the method by which 
a plant yielding rich food and forage and most 
delicious fruits has been produced, which, as 
much as any other plant, promises sooner or 
later to solve the present-day problem of higher 
living costs. 

"But," I have been asked, "do you mean that 
the cactus foresaw the coming of an enemy 
which was to destroy it? Is it believable that a 
plant, like a nation expecting war, could armor 
itself in advance of the necessity? And if the 
cactus did not know that an enemy was later to 
destroy it, would it not have been destroyed by 
the enemy before it had the opportunity of pre- 
paring a means of defense?" 

Let us look into the history of the plant and 
see the answer to these questions. 



ENVIRONMENT 75 

The facts are that parts of Nevada, Arizona, 
Utah, and northern Mexico were once a great 
inland sea that the deserts now there were the 
bed of that sea before it began its long process 
of evaporation. 

In these regions, so far as is known, all the 
North American cacti are supposed to have 
originated. 

Back in the ages before the evaporation of 
the inland sea was complete, the heat and mois- 
ture and the chemical constituents of the sandy 
soil combined to give many plants an opportu- 
nity to thrive. Among these was the cactus, 
which was an entirely different plant in appear- 
ance from the cactus of to-day, no doubt, with 
well-defined stalks and a multitude of thin leaves 
like other plants. 

As the heat, which had lifted away the in- 
land sea, began to parch the soil, the cactus 
with the same tendency that is shown by 
every other plant and every other living 
thing, began to adapt itself to the changing 
conditions. 

It gradually dropped its leaves in order to 
prevent too rapid transpiration of the precious 
life-supporting moisture. It sent its roots deeper 
and deeper into the damp substratum which the 
sun had not yet reached. It thickened its stalks 



IMPROVED AND WILD CACTI 
STILL BEAR LEAVES 

In the days of the long past and 
before the animals had begun their 
work of devastation, the plant had 
leaves like other plants. That this is 
so is evidenced by the fact that cactus 
slabs even now put forth these leaves in 
rudimentary form, the evidence of an 
old tendency which has not been entirely 
obliterated. Shortly after the tiny leaves 
come out, as shown in this color photo- 
graph print, they fall away to be fol- 
lowed by the spines which push out be- 
hind them. On all varieties these rudi- 
mentary leaves are soft and tender 
not spiny. 



ENVIRONMENT 77 

into broad slabs. It lowered its main source of 
life and sustenance far beneath the surface of 
the ground and found it possible thus to persist 
and to prosper. 

Perhaps there were, in the making of the 
desert, other plants not so adaptable as the 
cactus, plants which perished and of which man 
has no knowledge or record. 

And so, we may assume, the cactus and those 
other plants which adapted themselves to the 
new conditions crowded out those which were 
unable to fit themselves to survive under these 
gradually changing conditions. 

But there came animals to the bed of this one- ' 
time sea, attracted, perhaps, by the cactus and 
its contemporaries, which offered them food of 
satisfying flavor and easy access. 

Of the plants which had survived the evapora- 
tion of the sea and the heat of the broiling sun, 
there were many, quite likely, which failed to 
survive the new danger the onslaught of the 
animals. 

Species by species the vegetation of the desert 
was thinned out by the elements and by the 
animals; and the animals, with plant life to feed 
on, multiplied themselves in ever-increasing 
hordes, till perhaps the cactus was but one of a 
hundred plants to survive. 



78 LUTHER BURBANK 

Then came the fight of the cactus to outdo the 
beasts which sought to devour it the fight as a 
family, and the fight within the family to see 
which of its individuals should be found fit to 
persist. 

Of a million cactus plants eaten to the ground 
by ravenously hungry antelopes, we will say 
antelopes which had increased in numbers year 
by year while their food supply year by year was 
relentlessly dwindling of these million plants 
gnawed down to the roots, perhaps but a thou- 
sand or two had the stamina to throw out new 
leaves and to try over again. 

It is a well known fact that plants which are 
pliable enough to change their characteristics 
under changed conditions, more readily adapt 
themselves to still newer conditions. 

As in its previous experience, the cactus had 
changed the character of its stalk, so now it 
undertook another change the acquisition of an 
armor. 

This armor probably at first consisted of 
nothing but a soft protuberance, a modified fruit 
bud or leaf, perhaps, ineffectual in warding off 
the onslaughts of the hungry animals. 

So, of the thousand or two left out of the 
millions, there may have been but a hundred 
which were able to ward off destruction. 



ENVIRONMENT 79 

The hundred, stronger than the rest, though 
eaten to the ground were able still to send up 
new leaves, and with each new crop the hairs 
became stiffer and longer, the protuberances 
harder and more pointed, until finally, if there 
were even only one surviving representative of the 
race, there was developed a cactus which was effec- 
tually armored against its every animal enemy. 

One such surviving cactus, as transformed 
throughout ages of time, meeting new conditions 
with changes so slight perhaps as to be almost 
imperceptible, but gradually accommodating it- 
self to the conditions under which it lived and 
grew one such survivor out of all the billions 
of cactus plants that have ever grown would 
have been sufficient to have covered the deserts of 
America with its progeny to have produced all 
of the thorny cacti which we have on earth to-day. 

The cactus did not prepare in advance to meet 
an enemy it simply adapted itself gradually to 
changing environment as all vegetable and 
animal life on the earth must or perish. First, 
surviving the desert drought and the broiling 
sun, it threw its roots deep into the earth for the 
scanty moisture. Then, attacked by enemies 
which ate off the leaves, it still had life and re- 
sistance to try again. Ineffectually, at first, it 
began to build its armor, but each discourage- 



CONTRASTING TYPES OF 
CACTUS 

At the left, a colony of the spine- 
less cactus called the "Tapuna?*; at 
the right a quite different type called 
the "Tuna" Like all any spineless cac- 
tuses, these are crossbred seedlings; and 
they are of closely similar lineage, not- 
withstanding their widely different ap- 
pearance. An instance of the segrega- 
tion of hereditary characters. 



ENVIRONMENT 81 

ment proved but the incentive to another at- 
tempt. It is a vivid picture; the whole cactus 
family in a death struggle for supremacy over 
enemies which threaten its very existence - 
millions and millions of the family perishing in 
the struggle, and perhaps but one victorious sur- 
vivor left to start a new and armored race. 

It is wonderful, but whenever we plant a 
cactus slab to-day we see evidences of adapta- 
bility even more wonderful than this. 

The slab of cactus is an olive green color as 
we put it in the ground. It is flat, of an oval 
shape, an inch or less in thickness. Its internal 
structure is of a soft juicy texture like most 
succulent vegetables largely water, 

As the slab sends down roots, it begins to pre- 
pare itself to bear the burden of the other slabs 
which are to grow above it. 

The thin, flat shape thickens out until it is 
almost spherical; thus presenting a curved sur- 
face in four directions instead of in two, it braces 
itself against the winds which will endanger the 
tender new slabs far above it. 

Its tender woody fibers grow tough and re- 
sistant; it loses its velvety skin and develops a 
bark like that of a tree. 

Within a year after planting, this cactus slab 
will have changed in appearance and in char- 



82 LUTHER BURBANK 

acteristics to fit itself to the new conditions which 
surround it. 

It will have changed its structure to bear 
weight and stand strains. It will have modified 
its internal mechanism to transmit moisture in- 
stead of to store it. It will have remodeled its 
outer skin to protect itself from the ground 
animals from which it had no reason to fear 
destruction while growing higher up on the 
parent plant. 

Is it more wonderful that, unseen by us, a 
plant should have adapted itself to the desert 
and, through the ages, have armored itself 
against an enemy, than that, before our eyes, 
in a single year, it should meet changed condi- 
tions in an equally effective w r ay? 

Is it more wonderful that it should grow 
spines than it should grow slabs which in turn 
have the power to grow other slabs? 

Is not the really wonderful thing the fact that 
it grows at all? 

The cactus is one of the most plastic of plants 
educated up to this, perhaps, by the hardships 
and battles through which its ancestry has 
fought its way. 

A slip cut from a rosebush, for example, must 
be planted in carefully prepared ground of a 
suitable kind, at a certain season of the year, 



ENVIRONMENT 83 

with regard to moisture and temperature it 
must be watched and cared for until it takes root 
and is able to care for itself. The rose has evi- 
dently not had as severe a struggle as the cactus. 

But the cactus, having developed itself under 
the most discouraging conditions needs no such 
care. Every one of the fifty or more wartlike 
eyes on its every slab is competent to throw out 
a root, a fruit, or another slab whichever the 
occasion seems to warrant. 

Lay a cactus slab on hard ground, unscratched 
by a hoe, and the eyes of its under side will throw 
long white roots downward, while the eyes on 
the upper side await their opportunity, once the 
slab is rooted, to throw other slabs and blossoms 
upward. 

As the tiny buds grow from the eyes, it is 
impossible by sight or microscopic examination 
to determine which will be roots, which will be 
fruits, or which will be other slabs. It is as 
though the cactus, inured by hardship and pre- 
pared for any emergency, waits until the very 
last possible moment to settle upon the best- 
suited means of reproduction as though the 
bud, having started, becomes a root if it finds 
encouragement for roots, or a fruit if seed seems 
desirable, or an upward slab if this can be sup- 
ported. 



84 LUTHER BURBANK 

Nor does its attempt at reproduction require 
much encouragement. Fifty young cactus slabs 
laid on a burlap-covered wooden shelf four feet 
above ground were found to have thrown long 
roots down through the burlap and through the 
cracks of the boards within a few days. 

A cactus plant pulled from the ground and 
tied by a string to the branch of a tree remained 
hanging in the air for six years and eight months. 
During this time it had no source of nourishment 
and its slabs shriveled and turned a light brown. 
By planting these slabs in the ground they im- 
mediately took root and within a few weeks 
began to throw out buds and new slabs. 

A detached cactus slab, long forgotten in a 
closet, after having been in the dark for more 
than two years, was found to have thrown out a 
sickly looking baby slab. 

The more the adaptability of the present-day 
cactus and its tenacious hold on life are observed, 
the easier it becomes to understand its successful 
fight against its numerous enemies which lived 
during the desert-forming age, and to see the 
origin of the thorny cactus of to-day. 

Nor is the cactus the only desert plant which 
shows evidences of such a struggle. 

The goldenrods of the desert are more bitter 
than the goldenrods of the plains. 



ENVIRONMENT 85 

The wormwood of the desert is more bitter 
even than the wormwood which grows where 
there have been fewer enemies. 

The yuccas, the aloes, the euphorbias, all have 
counterparts in their families, which, needing 
less protection, show less bitterness, less poison, 
fewer spines. 

And even rare cactus plants from protected 
localities, and those of the less edible varieties, 
give evidence, by the fewness of their spines, that 
their family struggle has been less intense than 
the struggle of the cactus which found itself 
stranded in the bed of a former inland sea. 

Plants which have shown even greater adap- 
tive powers than the cactus are to be found in 
the well-known algse family. 

One branch of this family furnishes an apt 
illustration of the scant nourishment to which a 
plant may adapt itself. 

Microscopic in size, it lives its life on the upper 
crust of the Arctic snow storing up enough en- 
ergy in the summer, when the sun's rays liquefy a 
thin film of water on the icy surface, to sustain 
life in a dormant stage during the northern 
winter's six months of night. 

With nothing but the moisture yielded from 
the snow, and what nutriment it can gather from 
the air, this plant, called the red snow plant, 



VESTIGIAL LEAVES 

The projections here shown on one 
of the older slabs are vestigial leaves. 
An account of them, with reference to 
their evolutionary meaning, is given in 
this volume. They are all that remain 
of the leaves that the cactus once bore; 
and these reminiscent leaves drop off 
very shortly after coming out, leaving 
my new varieties as smooth as velvet. 



ENVIRONMENT 87 

multiplies and prospers to the extent that it 
covers whole hillsides of snow like a blanket 
covers them so completely that the reddish color 
of the plant, imparted to the snow, first gave rise 
to the tales of far northern travelers as to the 
color of the snowfall and explained the apparent 
phenomenon of red snow. 

Another division of this family, at the oppo- 
site extreme, thrives in the waters of Arrow- 
head Sulphur Springs in California lives its 
life and reproduces itself in water so hot that 
eggs may be easily cooked in it. 

In addition to these microscopic members, one 
thriving on the Arctic snows, the other in 
water at nearly the boiling point, there is still 
another member of this family which has formed 
the largest plant colony in the world. This, the 
gigantic growth of the Sargasso Sea, consists of 
a small seaweed wrenched from the coast and 
forms a huge tangled, floating mass. 

And so on; some of this family of the algae 
grow on and in animals, some on other plants, 
some on iron, some on dry rocks, some in fresh 
water, and some in the salt seas. 

The monkey-puzzle trees, Araucarias, show 
an adaptability to environment as striking as 
that of the cactus although for a wholly dif- 
ferent purpose. 



88 LUTHER BURBANK 

At the top of this monkey-puzzle tree, so 
called, are borne several very large cones con- 
taining the large nutlike seeds of the tree. 

In the case of the cactus the thorns were de- 
veloped to protect the plant itself from destruc- 
tion but in the case of the monkey-puzzle tree 
the animals threatened not the tree itself, but its 
offspring its nuts were so highly prized by the 
monkeys, and their number was so few, that it 
was forced to take protective measures to keep 
its seed out of the reach of enemies. 

From this we begin to see that each plant has 
its own family individuality, its own family per- 
sonality. Some plants, in order to insure repro- 
duction, produce hundreds or thousands of seeds, 
relying on the fact that in an oversupply a few 
will likely be saved and germinated; while other 
plants producing only a few seeds protect them 
with hard shells or bitter coverings, or, as in the 
case of the monkey-puzzle tree, with sharp spines 
at the tip of every leaf and all over the branches. 

In the deep canyons of California's mountains 
there grows a member of the lily family, the 
trillium. 

Near the bottom of these canyons there are 
places where the sunshine strikes but one side. 
The flowers on the shady side of the canyons are 
larger, and the leaves of the plants are broader, 



ENVIRONMENT 89 

and the bulbs are smaller and nearer the surface 
than those of the plants which grow where the 
sun reaches them. 

On the other side of the same canyons the 
bulbs grow larger and deep in the soil, and the 
leaves and the blossoms transform themselves to 
conserve moisture. 

Which was all that the cactus did when the sea 
was turned into a desert. 

About the geysers of Sonoma County, and 
scattered over other arid portions of California, 
Arizona, and Mexico, there are a group of pines 
(Pinus tuberculafaj muricata, attenuata, chihua- 
huana) having most remarkable characteristics, 
evidently having been subjected in long ages 
past to frequent fires, probably often started by 
the fires of this and other volcanic regions. The 
ground in the vicinity of the locality chosen by 
these pines is sometimes even yet so hot that it 
is difficult to walk over it, even with heavy boots, 
without burning the feet. There must have been 
a time, as all the evidence shows, when fires were 
quite common from volcanic action, and these 
pines have learned a lesson which no other pines 
or other coniferous trees on this earth have had 
to learn. 

The cones of most pines take two years in which 
to mature the seed, and all other pines open once 



A BEAUTIFUL FLOWERING 
CACTUS 

This is the cactus known as Opuntia 
basilaris, a low-spreading form that 
makes a very striking contrast with the 
giant spineless opuntias. The present 
species is too small to be of any value 
as a forage plant, but its flowers give it 
high rank as a border plant for the 
garden. The color of the flower is far 
more brilliant than the picture. 



ENVIRONMENT 91 

each two years at the proper season to distribute 
their seeds. The seeds of other pines do not re- 
tain their vitality and ability to grow even after 
the third year. The Geyser pines produce cones 
in great abundance in circles around the trunk 
and branches when much younger than other 
pines sometimes when only two or three feet 
in height. The cones of these pines remain 
closed on the trees so persistently that the new 
wood sometimes grows over them, surrounding 
them completely, but the seeds, even in these 
cases, remain in best growing condition after 
their long imprisonment in the wood. The cones 
never open to distribute the seed until a fire 
sweeps over the land, when those which have 
been gathering on the trees, perhaps for thirty 
or forty years, immediately open and soon after 
scatter the seed, from which the young pines 
often come up as thick as grass on a lawn. Of 
course some of these succumb to the crowding of 
their neighbors, but what a wonderful adaptabil- 
ity these pines have shown; a lesson which no 
other pine has been obliged to learn. In learn- 
ing these hard lessons which have become so 
deeply fixed in heredity, innumerable individuals 
have taken part, for time is generally the 
chief factor, and they can be fixed only by 
repetition. 



92 LUTHER BURBANK 

Let the cactus, battle-scarred and inured to 
hardship, teach us our first great lesson in plant 
improvement : 

That our plants are what they are because of 
environment; that simply by observing their 
structures, their tendencies, their habits, their in- 
dividual peculiarities, we can read their histories 
back ages and ages before there were men and 
animals read it, almost, as an open book; that 
our plants have lived their lives not by quiet 
rote and rule, but in a turmoil of emergency; 
and, just as they have always changed with their 
surroundings, so now, day by day, they continue 
to change to fit themselves to new environments ; 
and that we, to bring forth new characteristics in 
them, to transform them to meet our ideals, have 
but to surround them with new environments 
not at haphazard, but along the lines of our 
definite desires. 



It is far more wonderful even that 
plants grow at all than that they 
can so readily adapt themselves to 
changing conditions. 



TWENTY-THREE POTATO 

SEEDS AND WHAT 

THEY TAUGHT 

A GLIMPSE AT THE INFLUENCE OF 
HEREDITY 

THE springtime buds unfold into leaves 
before our eyes without our seeing them 
unfold. We have grown accustomed to 
look for bare limbs in March ; to find them hidden 
by heavy foliage in May; and because the process 
is slow, and because it goes on always, every- 
where about us, we are apt to count it common- 
place. 

Just as we can understand that the tree in our 
yard, responding to its environment to the 
April showers, to the warm noons of May, to the 
heat of summer and to the final chill of fall has 
completed a transformation in a year, so, too, 
can we more easily understand the gradual trans- 
formation of the cactus in an age. We can also 
realize that the individual steps between the first 
ineffectual hairy protuberance, and the final 

93 



94 LUTHER BURRANK 

spiny armor, each a stronger attempt to respond 
to environment, were perhaps so gradual as to 
be imperceptible. 

But those rudimentary, half-formed leaves 
which come forth from every eye of the cactus 
slab before the thorns or fruits come out those 
leaves which, no longer serving any useful pur- 
pose, soon turn yellow, die, and fall off which 
environment has acted to reject though once 
of fundamental importance to the plant? 

And those two smooth slabs that push out 
when the tiny seedling has just poked its thorny 
head above the ground why should they be 
smooth while the first central leaf is thorny? 

How shall we account for this tendency in a 
plant to jump out of its own surroundings, and 
out of the surroundings of its parents, and their 
parents and those before them and to respond 
to the influences which surround an extinct an- 
cestor to hark back to the days when the desert 
was the moist bottom of an evaporating sea and 
before the animals came to destroy? 

A group of scientists were chatting with me 
once when a chance remark on heredity led one 
of them to tell this bear story: 

It seems that a baby bear had been picked up 
by miners within a few days after its birth be- 
fore its eyes had opened. The cub, in fact, was 



INFLUENCE OF HEREDITY 95 

so small that it was carried several miles to the 
camp tied in the sleeve of the coat of one of the 
miners. 

Raised to adult bearhood by these miners, 
without ever having seen another bear relieved 
of the necessity of finding its own food and re- 
moved from the wild environment of its ancestors 
this bear had become as thoroughly domesti- 
cated, almost, as a tabby cat. 

What would such a bear do if thrown on its 
own resources? Would it have to begin at the 
beginning to learn bear-lore? 

Bears are great salmon fishers, for example. 

But is this skill taught by the mother to the 
baby bear or is it a part of every bear at birth? 
That was the question of interest. 

When the animal had arrived at maturity, it 
was taken, one day, to a shallow salmon stream. 

Here was a bear which had never fished for 
salmon, and had never tasted fish ; a bear which, 
if bears have a language, had not received a 
moment of instruction in self-support; a bear 
which, taken before its eyes were open, had never 
seen its mother, had never known an influence 
outside of the artificial atmosphere of the mining 
camp. 

Brought to the salmon stream, however, there 
was not an instant of delay; it glanced about, 



96 LUTHER BURBANK 

located a natural point of vantage, straddled the 
brook with its face downstream, and bending 
over, with upraised right paw, waited for the 
salmon to come. 

It did, unhesitatingly, just what any normal 
wild-raised bear would have done. 

With wonderful dexterity it was able to scoop 
the onrushing salmon out of the stream and to 
throw them in an even pile on the bank with a 
single motion. 

As other bears would do, this domesticated 
bruin stood over the stream until it had accumu- 
lated a considerable pile of the salmon on the 
bank. 

Going to this pile it quickly sorted over the 
fish, making now two piles instead of one with 
all the male salmon in one pile and all the female 
salmon in the other. 

Then, with its sharp claw, it proceeded to 
split open the female salmon and to extract 
the roe, which it ate with relish. This con- 
sumed, it finished its meal on the other meat 
of the fish. 

Untaught, it recognized salmon as food; dis- 
tinguished males from females ; knew the roe as 
a special delicacy. Unpracticed, it knew, in- 
stantly, just how to fish for salmon and how to 
find the roe. 



IXFLUEXCE OF HEREDITY 97 

Right here on this experiment farm you may 
find hundreds of evidences of heredity more 
striking than that more striking because they 
are the evidences of heredity in plant life, in- 
stead of in animal life. 

Here you will find plants which show tenden- 
cies unquestionably inherited from a line of an- 
cestry going back perhaps ten thousand years 
or more tendencies, some of them, which now 
seem strangely out of place because the condi- 
tions which gave rise to them in their ancestors 
no longer exist; tendencies like those of the 
cactus, the rose, and the blackberry to protect 
themselves from wild beasts when wild beasts are 
no longer enemies ; tendencies to deck themselves 
in colors designed to attract the insects of a for- 
gotten age insects which, perhaps, no man has 
ever seen. 

SVhere some incredulity might be expressed 
as to whether the bear had not actually been 
taught to fish for salmon, or seen another bear 
perform the act, there can be no such question 
in the case of heredity in plants. 

Here in this bed of sweet peas is a plant which 
has inherited the climbing, twining tendency. 

This is an evidence that, at some time back in 
its history, this plant has probably been crowded 
for room. Plants which grow high do so usually 

Vol. 1 Bur. D 



98 LUTHER BURBANK 

because, at some stage in their existence, they 
have had to grow high to get the sun and air 
which they need. Low-lying plants, like the 
pumpkin for example, give evidence that they 
have always enjoyed plenty of space in which 
to spread out. 

It might be thought that the bear in the story 
may possibly have slipped away, unknown to its 
keepers, and seen another bear fish for salmon; 
but if these tendencies and traits, and if the 
ability to perform the feats necessary for exist- 
ence are not passed down from mother to son 
if they do not come down through the line of 
ancestry, if all of the old environments of the 
past have not accumulated into transmissible 
heredity, what enables that sweet pea to 
climb upon some support to reach the needed 
light? 

A closer observation of the sweet pea will show 
us that its tendrils are really modified leaves, 
produced like the spines of the cactus, by ages of 
environment which, added up, combine to make 
heredity; and that their actual sensitiveness to 
touch is so highly developed that they adroitly 
encircle and hold fast to any suitable support 
within their reach. 

It would be interesting to take a motion 
picture of the sweet pea as it grows, as similar 



INFLUENCE OF HEREDITY 99 

motion pictures have been taken; making sepa- 
rate exposures, one every three minutes instead 
of fifteen or sixteen to the second, so that the 
reel would cover a period of fifteen days;- then, 
with a fifteen-day history recorded on the film, to 
run it through the projecting lantern at the rate 
of fifteen or sixteen pictures to the second, thus 
showing in seven or eight minutes the motions 
of growth which actually took fifteen days to 
accomplish; on the screen before us, with quick 
darting motions, we should see the sweet pea 
wriggle and writhe and squirm we should see 
it wave its tendrils around in the air, feeling out 
every inch within its reach for possible supports 
on which to twine. 

We should see, by condensing half a month of 
its life into an eight-minute reel, that this sweet 
pea has inherited an actual intelligence slow in 
its operation, but positive, certain an inherited 
intelligence which would be surprising even in 
an animal. 

Throughout all plant life we find these unde- 
niable evidences of environment having affected 
heredity. 

Here, for example, are two tiny seedlings 
which look almost alike. They are distinctly 
related. One is the acacia (A. mollissima) and 
the other the sensitive plant (Mimosa pudica). 



100 LUTHER BURBANK 

Much as these plants look alike, they bear 
witness to the fact that they have within them 
two entirely different strains of heredity. 

The acacia will permit us to touch it and 
handle it without showing signs of disturbance. 

But its cousin in the same soil, and of the same 
size, immediately folds up its leaves, in self-pro- 
tection, at the slightest touch. 

From this we read the fact that one branch of 
this family has found it necessary to perfect a 
form of self-defense, while the other has had no 
such experience in its life history. 

The acacia being a tree which grows out of 
the reach of browsing animals, while the sensitive 
plant is a low-growing succulent tender plant, 
the acacia needs no thorns, and has none, while 
the sensitive plant has the added defense of 
numerous thorns. 

I have been much interested lately in an ex- 
periment with clover in producing clover leaves 
with wonderful markings. 

The only way in which I can account for the 
markings with which some clover leaves will be- 
deck themselves is that, in the heredity of the 
plant, there was a time when, not being poison- 
ous itself, it tried to simulate the appearance of 
some poisonous plant to protect itself from 
insects or other enemies. 



INFLUENCE OF HEREDITY 101 

At first thought it might require a stretch of 
the imagination to understand how this could be 
yet a closer inquiry shows that the process was 
as gradual and as surely progressive as the trans- 
formation of the cactus. 

In clover, as with all other plants, there has 
always been variation some few individuals 
have always had the white and black markings. 

At some time in the history of the plant those 
without the markings may have been destroyed, 
and so, responding to this new environment, the 
markings became more and more pronounced 
until now we have not only white triangular 
markings, but deep black splotches and red and 
yellow colors intermixed in curious figures. 

From these markings we can readily imagine 
the history of this Chilean clover most of the 
family having plain leaves inherited from an 
ancestry which found no need to protect itself 
from an enemy with an occasional outcropping 
of poisonous-looking color splotches the inher- 
itance of environments in which self-protection 
was necessary. 

Or we might consider the ice plant (Mesem- 
bryanthemum crystallinum) which protects it- 
self from the heat and evaporation of the sun by 
surrounding itself with tiny water droplets which 
have the appearance of ice; or the wild lettuce, 



102 LUTHER BURBANK 

known sometimes as the compass plant, which 
turns its leaves north and south so that only their 
edges are reached by the sun ; or any of a number 
of other strange protective measures which 
plants have perfected all manifestations which 
would be impossible if heredity were not an ever- 
present, controlling influence. 

We have, too, in many parts of the country, 
plants which have learned to snare and trap in- 
sects and even small animals and with a secretion 
somewhat resembling gastric juice to digest them 
and from them obtain an added supply of 
nourishment. 

Among these carnivorous plants are the com- 
mon pitcher plants. 

The pitcher plants, instead of belonging to 
only one species, are to be found having this habit 
developed in several species, thus showing that 
environment has produced a similar strain of 
heredity in the several species. 

One of the pitcher plants (Darlingtonia call- 
jornicd] which grows abundantly in the moist 
meadows of the Sierras in northern California 
even catches frogs, mice, and other small animals, 
and sometimes even birds. The plant is especially 
equipped to lure its prey into its pitchers. Above 
the pitcher is a little latticed window, through 
which the light can shine. The insects and the 



INFLUENCE OF HEREDITY 103 

animals see a haven from the sun and rain, and 
as they go in, there are long sharp little fingers 
all pointing inward and downward, under the 
latticed window, just right to hasten and project 
its prey into the pool of water inside the pitcher, 
prepared for this very purpose. 

In these traps it is common to find all kinds 
of insects including the undigested wings and 
legs of beetles and grasshoppers, and sometimes 
the bones of toads and frogs. 

Is this not a more wonderful manifestation of 
odd environment, recorded within a plant in the 
form of heredity, than even that of the bear 
w r hich seemed to have inherited the intelligence 
and skill to fish? 

"To my mind," said one of the scientists, "the 
by-product of your work is fully as interesting 
as the work itself the viewpoint which you get 
on the forces which control life is of even greater 
attraction to me than the wonderful and useful 
productions which you have coaxed from the 
soil." 

But hardly a by-product, for these things are 
a vital part of the day's work. Heredity is more 
a factor in plant improvement than hoes or 
rakes ; a knowledge of the battle of the tendencies 
within a plant is the very basis of all plant im- 
provement. It is not, as one might think, that 



THIS PLANT EATS AND 
DIGESTS INSECTS 

The pitcher plant (Darlingtonia) 
shown here, which grows in the high 
mountains of California, has perfected 
an ingenious contrivance for catching 
and digesting insects. At the top of the 
pitcher, so called, seen above, there is an 
opaque lattice work in the interstices of 
which is a translucent, micalike sub- 
stance. The insect, entering from be- 
neath in search of shelter, finds itself in 
a cosy chamber, well lined and weather- 
proof. Once inside the chamber, how- 
ever, it discovers that it is being swal- 
lowed, irresistibly, and the plant finally 
deposits it in the stomach below, where 
it digests it with a secretion akin to 
hydrochloric acid. There are several 
other known carnivorous plants, show- 
ing that at some time in their ancestry 
the soil has not given them sufficient 
nutriment for their needs. 



INFLUENCE OF HEREDITY 105 

the work of plant improvement brings with it, 
incidentally, a knowledge of these forces. It is 
the knowledge of these forces, rather, which 
makes plant improvement possible. 

There are really, after all, only two main in- 
fluences which we need to direct, in order to 
change and control the characteristics of any 
individual growing thing. 

The first of these is environment. 

Rains, snows, fogs, droughts, heat, cold, 
winds, the change in temperature between night 
and day soil, the location in shade or sun 
competition for food, light, air the neighbors, 
whether they be plant neighbors, or animal 
neighbors, or human neighbors all of these, and 
a thousand other factors which could be men- 
tioned, are the elements of environment some 
pulling the plant one way and some another, 
but each with its definite, though sometimes 
hardly noticeable, influence on the individual 
plant. 

And the second is heredity! 

Which is the sum of all of the environments 
of a complex ancestry back to the beginning. 

Just as with the bear, so in plant life. In 
every seed that is produced there are stored away 
the tendencies of centuries and centuries of an- 
cestry. The seed is but a bundle of tendencies. 



106 LUTHER BURBANK 

When these tendencies have been nicely bal- 
anced by a long continuation of unchanging 
environment, the offspring is likely to resemble 
the parent. 

But when, through a change of environment, 
or through crossing, that balance is disturbed, 
no man can predict the outcome. 

So when such a seed is planted, no man can 
be sure whether the twentieth-century tendencies 
will predominate, or whether long-forgotten 
tendencies may suddenly spring into prominence 
and carry the plant back to a bygone age, in 
some of its characters. 

"How can seeds store up the tendencies of 
their ancestry?" some one has asked. 

"How can your mind store up the impressions 
which it receives?" we reply. 

Hidden away in the convulsions of our own 
brains, needing but the right conditions to call 
them forth with vividness, there are hundreds of 
thousands, perhaps millions of impressions which 
have been registered there day by day. 

The first childhood's scare on learning of 
the presence of burglars in the house may 
make us supersensitive to night noises in middle 
age. 

The indelible recollection of a mother's love 
and tenderness may arise after forty years to 



INFLUENCE OF HEREDITY 107 

choke down some harsh word which we are about 
to utter. 

The combined impressions of a thousand ex- 
periences with other human beings seem to blend 
together to help us form our judgment of a 
single human being with whom we are about to 
deal. 

As the weeks have rolled into months, and as 
the months have melted into years, new impres- 
sions have arisen to crowd out the old; strong 
impressions have supplanted the weak, bigger 
impressions have taken the place of the lesser 
ones but the old impressions are always there 
always blending themselves into our judg- 
ments, our ambitions, our desires, our ideals 
always ready and waiting, apparently, to single 
themselves out and appear before us brilliantly 
whenever the proper combination of conditions 
arises. 

So, too, with the seed. 

Every drought that has caused hardship to 
its ancestors is recorded as a tendency in 
that seed. 

Every favoring condition which has brought a 
forbear to greater productiveness is there as a 
tendency in that seed. 

Every frost, every rain, every rise of the morn- 
ing sun has left its imprint in the line of ancestry 



A NEW PLUM AND ITS 
WILD ANCESTOR 

When plants grow wild there is little 
need for large quantities of luscious 
meat; but as they come under cultiva- 
tion the stone grows less and the meat 
not only more, but better. This direct- 
color photograph print is of one of my 
largest hybrid plums and of a wild 
plum, such as grows in the woods near 
Santa Rosa; both are the actual size. 
The large one was raised from the seed 
of the small one here shown. 



INFLUENCE OF HEREDITY 109 

and helped to mold tendencies to be passed on 
from plant to plant. 

Beneath the wooden-looking, hard-sheathed 
covering of the seed, there is confined a bundle 
of tendencies an infinite bundle and nothing 
more to give its product character. 

One tendency stronger than another perhaps 
a good tendency suppressing a bad tendency 
or the other way, tendencies inherited from 
immediate parents, tendencies originating from 
the influences of twenty centuries or more ago 
tendencies which are latent, awaiting only the 
right combination of conditions to bring them 
to life; all of the tendencies of a complex ances- 
try some lulled to sleep, but none obliterated; 
that is a seed. 

The whole life history of a plant is stored away 
in its seeds. 

If we plant a great number of the seeds we 
shall be able to read more or less clearly its life 
history with its variations, its hardships, all of its 
improvements and retrogressions uncovered be- 
fore us. 

Who knows what little thing will change 
a career? Or what accident will transform 
an ideal? Or what triviality, out of the or- 
dinary, will lead to the discovery of a new 
truth? 



110 LUTHER BURBANK 

The potato seed ball is an insignificant-looking 
fruit, of no use as any ordinary practical farmer 
would have said. 

Away back in the history of the potato, on 
the bleak Chilean mountainsides where it had 
to depend almost wholly upon its seeds instead 
of tubers for reproduction, every healthy potato 
plant bore a great number of seed balls and this 
is the case even at the present time in the high 
Andean region and down in the canyons and 
valleys of Chile, wild potatoes are one of the 
worst of weeds, though in some cases producing 
fairly good small potatoes. 

But years of cultivation have removed from 
the potato the necessity of bearing seeds for the 
preservation of its race. The potato plant, so 
certain now to reproduce itself through subdivi- 
sion of its tuber, so reliant on man for its propa- 
gation, has little use for the seed upon which 
its ancestors mostly depended for perpetuation 
before man relieved it of this burden. 

So the average potato grower, knowing that 
next year's crop depends only on this year's 
tubers and being more anxious, alas, to keep 
his crop at a fixed standard than to improve it 
might see the occasional seed ball without 
knowing its meaning or realizing its pos- 
sibilities. 



INFLUENCE OF HEREDITY 111 

I had been raising potato seedlings for amuse- 
ment at Lancaster, Mass., in 1862 and 1863, but 
all the potato seedlings which I had raised had 
so generally almost exactly resembled the parent 
plants that I had given up the effort to produce 
anything of special value from any of the com- 
mon varieties. 

No one, up to the present time, as far as we 
have learned, has ever seen a seed ball on the 
Early Rose potato, except myself, and for years 
I had a standing offer of five dollars per fruit 
for anyone who would furnish me another from 
the thousands of acres which were raised of this 
variety at that time. 

This seed ball attracted my attention from 
knowing that the Early Rose did not bear seeds 
and it was watched patiently from the time it 
first formed on the vine until it was nearly ripe. 

When one day I went to examine it, as I did 
often, it had disappeared and every effort to find 
it for a time failed, but at last it was discovered 
a short distance from the plant where perhaps 
a bird, a dog, or some other passing animal had 
brushed it from the vine. 

Although I was raised on my father's two- 
hundred-acre farm a large one for New Eng- 
land and began my experiments there, yet my 
own little twenty-acre farm in an adjoining town 



112 LUTHER BURBANK 

has, by the product of the "Burbank" potato, 
increased the wealth of the world very greatly, 
and this without the cost of a dollar except the 
$150 which I received for it from a well-known 
eastern seedsman. 

In the month of May, 1872, in this little New 
England town, I held in my hand one seed, ten 
of which were not as large as an ordinary pin 
head. From this tiny seed the "Burbank" potato 
came. More than six hundred million bushels of 
this potato have been raised during the past 
forty-nine years ; enough to make up a solid train 
of potatoes to reach 14,500 miles, or more than 
halfway around this planet. 

1 The interesting fact to be noted here is that 
from this seed ball were produced twenty-three 
new potato plants. 

* Each of these plants yielded its own individual 
variations, its own interpretation of long-for- 
gotten heredity and numerous natural crossings. 

One, a beautiful, long, red potato, decayed 
almost as soon as dug; another was red-skinned 
with white eyes; another white with red eyes; 
two white ones and several had eyes so deep that 
they were unfit for use, and all varied widely. 

These twenty-three variations, in fact, may 
have represented as many different stages in the 
history of the potato family; and, having no 



INFLUENCE OF HEREDITY 113 

present-day environment to hold them in balance, 
all were more or less unlike any potato which 
had ever been cultivated. 

Among the number, though, was one variety 
better than the rest and better than any potato 
which had ever been seen. This variety was 
named the "Burbank" by J. J. H. Gregory, a 
well-known seedsman of eastern Massachusetts. 

With the same work indeed with less both 
the pioneer who grew potatoes for his own sus- 
tenance, and the potato specialist who produced 
his crop on a commercial basis, were now enabled 
to very considerably increase their output. 

And to-day, when more pounds of potatoes 
are grown than of any other food crop of the 
world, the increase made in a single year's 
crop the increase gained without any corre- 
sponding increase in capital invested or cost 
of production amounts to an astounding sum 
in the millions. 

Possibly at no other time in the history of the 
nation could the Burbank potato have come 
more opportunely. 

These were the days when Chicago was a far 
western city, and when the great territory be- 
yond was the home of the pioneer. 

The potato is a vegetable designed peculiarly 
for the pioneer. 



THE BURBANK POTATO 

An improvement in one of the most 
important of crops. This variety has 
added many millions to the wealth of 
this and other countries, not only by its 
unusual vigor and productiveness, but 
by its superior quality. Millions of 
bushels of this variety are grown 
annually. 



INFLUENCE OF HEREDITY 115 

It requires no great preparation either for 
planting or harvesting. It grows rapidly on the 
rich new soil turned over by the settler; a little 
cultivation insures its growth; when ripened it 
may lie in the ground and be used as needed; 
when the fall frosts come it can easily be banked 
in a pit for winter use. 

Little care; small outlay; easy preparation 
for food; these make the potato among the first 
crops to be grown when the settler locates his new 
home. 

Trace now the influence which this one success 
had upon a growing nation. It was in 1872. It 
was a time when the line between success and 
failure between starvation and comfortable 
plenty was drawn so finely for the pioneer that 
even the slightest help was of a value out of 
proportion to its intrinsic worth. 

A crop failure or shortage, in those recon- 
struction days after the war, meant a set-back 
that would take years to overcome, for the 
pioneer's only source of supply, usually, was his 
own crop. 

Any increase, therefore, in nature's products 

such as the potato in the days of the pioneer, 

signified more to the world than it ever has since. 

The greatest value it gave the greatest service 

it performed was to help the world to know the 



118 LUTHER BURBANK 

Surrounding this neatly packed nest of eggs 
with its single upright stalk, and hugging it 
closely all around, we should see very slender 
modified leaves, half an inch or so in length, end- 
ing each in a pointed stalk as large around, 
perhaps, as a bristle out of a hairbrush, arranged 
in circular form as if shielding the egg chamber 
and its central stalk from harmful intruders. 

At the top of the surrounding stalks we should 
see crosswise bundles, nicely balanced, or beauti- 
ful slaty gray pollen dust, loosely held in half- 
burst packages. 

At their base we should find the dianthus 
honey factory, also the fragrance factory a 
group of tiny glands which manufacture a sticky 
confection that covers the bottom of the flower 
with its sweetness and fragrance. 

Shall we take one of the egglike seeds from 
its nest and plant it? We might as well plant a 
toothpick. 

Shall we take a package of the pollen, and put 
it into the ground? We might as well sow a 
pinch of flour. 

But let us combine a grain of that pollen with 
one of those eggs and ten days in the soil it will 
show us that we have produced a living, growing 
thing a new dianthus plant, with an individ- 
uality, a personality of its own an infant dian- 



INGENUITY IN VARIATION 119 

thus, which we for the first time have brought 
into being a thing which had never lived before, 
yet which has within it all of the tendencies in- 
herited from ages of ancestry which wait only 
on environment to determine in a slight degree 
which shall predominate. 

By the simple combination of the pollen and 
the egg we have produced a new individual which 
may, if we have the requisite knowledge in choos- 
ing the parents and will it, become the founder 
of a whole race of new and better carnations. 

How shall we go about it to make a combina- 
tion such as this between the pollen dust and 
the seedlike egg so snugly stowed away within 
its nest? 

Let us examine that central stalk inside the 
guard of pollen-bearing stamens and few or 
many petals, and we shall have the answer. 

As the stamens fall away we begin to see a 
transformation in the central stalk. Its upper 
end, which at first was single, now shows a tend- 
ency to divide into two or three curling tendrils 
moist and sticky, covered with hundreds of 
little fingers to still further catch and hold the 
pollen. 

Though we may plant pollen in the ground 
without result, we have but to place it on one 
of these stigmas as they curl from the end of 



THE GERANIUM READY TO 
RECEIVE POLLEN 

As soon as the pollen has been re- 
moved by insects from the geranium, its 
anthers and stamens shrink and wither 
away, disclosing the pistil which, they 
have surrounded. The pistil then un- 
coils into five curling lobes, upon whose 
sticky surface the pollen from other 
flowers finds lodgment. 



INGENUITY IN VARIATION 121 

that central pistil stalk to start an immediate and 
rapid growth. 

Once planted there, the pollen grain begins to 
throw out a downward root, into and through 
the pistil stalk forming itself into a tube which, 
extending and still extending, finally taps the 
egg chamber and makes possible a union be- 
tween the nucleus of that pollen grain and the 
egg below r which awaits its coming. 

So, to produce a new dianthus, we have but to 
dust the grains of pollen upon the stigma of that 
central pistil stalk; and when the flower has 
withered away, its duty done, we shall soon find 
within the egg chamber a package of fertile 
dianthus seeds ready for planting. 

But there arises now a difficulty. While 
those little packages of pollen dust are there, 
the central pistil stalk inside keeps shut up 
tight, and it has no sticky surface on which to 
dust the pollen and no little fingers to catch 
and hold it. 

And if we search for another blossom which 
shows an open, sticky pistil, we shall always find 
that the pollen packages which once surrounded 
it have passed away. 

To make a combination between the pollen 
grains and the egglike seeds, therefore, we find 
it necessary to search first for one blossom which 



122 LUTHER BURBANK 

is in its pollen-bearing stage, and then for 
another blossom which has passed this point and 
shows a receptive stigma we are forced to make 
the combination between the two, instead of be- 
tween the pollen grains and the eggs of the same 
blossom. 

If the stigma of a blossom were at its receptive 
stage when the pollen packages around it were 
bursting open, there would probably be com- 
bined in the seeds of its egg chamber below only 
the characteristics of one parent plant only 
the tendencies of a single line of ancestry. 

But when these eggs have brought to them the 
pollen from another plant, there are, confined 
within them, the tendencies and characteristics 
of two complex lines of ancestry; so that the 
plants into which they grow will be encouraged 
into variation and individuality, not as a result 
of environment alone, but as a result of the 
countless tendencies inherited from two separate 
lines of parentage. 

What a scheme for pitting the old tendencies 
of heredity against the new tendencies of en- 
vironment what an infinite possibility of com- 
binations this opens up! 

Truly, of a million dianthus blossoms no two 
could be exactly alike nor any two of their 
millions of petals nor any two of their millions 



INGENUITY IN VARIATION 123 

of stamens nor any two of their millions of 
honey glands nor any two of their thousand 
million pollen granules. 

What we have seen in the dianthus those 
egglike seeds, the sticky stigma and that micro- 
scopic pollen dust, we may see in some form or 
other in every flowering plant that grows. 

The act that we might have performed to pro- 
duce a new dianthus plant the combination of 
the pollen with some of those eggs is going on 
about us always, everywhere by the bees, the 
butterflies, the birds, the winds, and numerous 
ether agencies acting to effect these combina- 
tions. Which is the reason for the candy factory 
at the bottom of every carnation's little central 
well. And for those brilliant petals, and that 
delicate fragrance and the arrangement of the 
stamen stalks, and the crosswise poise of their 
pollen-bearing anthers, and the central pistil 
stalk which rises upward from the egg nest and 
everything that is beautiful and lovely in the 
bloom of that dianthus and the dianthus itself. 

Here is a plant, the dianthus, so anxious to 
produce variations in its offspring that it has lost 
the power of fertilizing its own eggs and risked 
its whole posterity upon the cooperation of in- 
sects or other means for bringing pollen from 
some neighboring plant. 



A POLLEN-LADEN BEE 

This direct-color photograph print 
shows a bee, greatly enlarged, which was 
captured in a cactus flower. The pollen 
grains can be seen sticking to its hairy 
body, and the fact that, as it crawls into 
the next flower, some of this pollen will 
find lodgment on the sticky surface of 
a receptive stigma is easily realized. 
The bees gather pollen not only for 
distribution but for their own uses. The 
two large splotches of pollen shown be- 
neath the second pair of legs are ff pollen 
dough" or (C bee bread" which the bees 
carry home for food. 



INGENUITY IN VARIATION 125 

It has no power of locomotion no ability to 
get about from place to place in search of pollen 
for its eggs or of eggs in need of its pollen; nor 
has its neighbor, so they call in an outside mes- 
senger of reproduction the bee. 

The dianthus secretes its honey at the base of 
its blossom. It places movable packages of pol- 
len dust balanced on springy stamens in such a 
way that, to reach the sweets, the pollen hedge 
must be broken through. It keeps its egg cham- 
ber closed and its pistil unreceptive while the 
pollen dust is there, and, as if to advertise its 
hidden sweets to the nectar-loving bees, it throws 
out shapely petals of many brilliant hues and 
exudes a charming fragrance. 

And thus the bees, attracted from afar, crowd- 
ing into the tiny wells to get their food, become 
besmeared with pollen dust as they enter a pollen- 
bearing bloom and leave a load of pollen 
dust wherever they later brush some receptive 
stigma. 

Why did the dianthus gets its color? 

For the bees. 

Just as the cactus covered itself with spines 
until it had built up an effective armor, in the 
same way the dianthus, by easy stages, has 
worked out a color scheme to attract the bees 
upon which it depends to effect its reproduction. 



126 LUTHER BURBANK 

On my Sebastopol farm there was once 
growing an arum (A. dracunculus] whose 
color and scent reveal a somewhat different 
history. 

Unlike most flowers which advertise them- 
selves by a pleasing fragrance to attract bees, 
birds, and butterflies, this plant produces a scent 
to attract carrion flies. 

Some flies feed on carrion. The nectar of the 
clover is not to their liking and the brilliant 
colors of our garden flowers fail to attract them. 
Our refuse is their food, and they are guided to 
it by colors and scents which are highly offensive 
to us. 

So this arum, or carrion lily, as it has been 
named stranded at some time in its history, 
perhaps, in some place where flies were its only 
available messengers of reproduction, or bloom- 
ing at a period when other means were not 
within its reach has bedecked its spathe with 
a brownish-purple color, resembling the color 
and texture of a piece of liver or an overripe 
beefsteak. 

Just as the dianthus supplements its advertise- 
ment in color with an advertisement in fragrance, 
so the carrion lily has developed an individual 
odor appeal, decidedly like that of meat of un- 
certain age and quality. 



INGENUITY IN VARIATION 127 

So obnoxious and so penetrating is the odor 
of this flower that each year it has been found 
necessary to cut off and destroy the blooms as 
soon as they appear. 

And so truly has it achieved its ideal that even 
the buzzards, carrion birds that they are, at- 
tracted by its color, its texture, and its smell, 
have descended in ever-narrowing circles only to 
fly away in disgust when they found they had 
been lured by a flower. 

Where the dianthus finds it satisfactory 
merely to block the entrance to its honey store 
with an array of pollen bundles which must be 
pushed aside by the entering insect, the carrion 
lily makes doubly sure of pollination by means 
of a still more ingenious device. 

The fly, attracted by the color of the spathe 
and guided by the hidden odor at the base of the 
flower, lights on the sturdy spadix and uses it 
as a ladder for descent. The opening around the 
spadix is just large enough to afford a comfort- 
able passageway; but once within the well, the 
spathe closes in and snugly hugs the spadix, so 
that the fly, buzzing about in the chamber 
below, becomes thoroughly covered with the 
pollen dust. 

This done, the flower slowly unfolds and per- 
mits the pollen-laden insect to escape. 



ARUM DRACUNCULUS A 
FLY-LOVING FLOWER 

The carrion lily pictured here adver- 
tises to the flies to act as its messengers 
of pollination. The spathe frequently 
grows to fifteen inches in length, and 
as can be seen, though rich and almost 
attractive in appearance, is of the same 
color as a piece of decaying liver. The 
smell emitted from this flower is offen- 
sive in the extreme all for an adver- 
tisement for flies, which surround the 
plants in great numbers when in bloom. 



INGENUITY IN VARIATION 131 

white or yellow luminous colors always to 
attract the moths that fly after the sun goes 
down. 

As far as I have observed, no flower which 
blooms exclusively at night has any other color 
except yellow or white. 

We should find many interesting half hours 
of wonder contemplating such flowers as the 
honeysuckle, the nasturtium, the aquilegias, 
some clovers, and many of the lilies which have 
taken special precaution to place their nectar ir 
long, hornlike tubes, out of the reach of most 
insects, so that only the birds or insects with an 
unusually long proboscis may become their mes- 
sengers of reproduction. 

We should see the pathos of those flowers 
which advertise for insects that rarely come. The 
barberry, for example, which can be pollinated 
only during the bright hours of a cloudless day, 
and during a time so short that there is little 
chance of pollen being brought by insects from 
other blossoms. Each barberry blossom, read} 
for the insect if it should come, but as if expect- 
ing disappointment, makes sure of self-perpetua- 
tion, if not of self -improvement, by jabbing its 
pollen-laden anthers on its own stigma with a 
motion as positive and as accurate as the jump of 
a cat. 



132 LUTHER BURBANK 

Or the fennel flower (Nigella) of France, in 
which the several pistils bend over and take 
pollen from the stamens around them and 
straighten up again. 

Or the flowers of the nettle (Urtica) in which 
the stamens increase their height with a sudden 
springlike action, showering the pollen up over 
the receptive stigma. 

We should observe that wheat and most of the 
similar other grains, as though discouraged by 
centuries of collective cultivation, or failure to 
secure individual selection, had settled down to 
the steady task of reproducing their kind almost 
exactly alike, depending on similar individual 
environment for slight individuality, and insur- 
ing reproduction for self-pollination, with rare 
exceptions. 

We should see plants in all stages of their 
attempts to keep their kind fully adapted to 
their new and constantly changing environments ; 
we should see a range of ingenuity so great that 
no man, no matter how many of his days have 
been devoted to the study of plants and their 
ways, can ever become weary of its wonders. 

"I bought some extremely expensive seed corn 
several years back," complained a Santa Rosa 
farmer. "But, just as I expected, it ran down. 
The first year's corn was fine, and so was the 



INGENUITY IN VARIATION 133 

second; but now it has gone clear back to 
ordinary corn. This plant improvement does 
not pay." 

Do you know how corn reproduces itself? 

Do you realize that if you plant good corn on 
one side of the fence and inferior corn on the 
other, the corn cannot see the fence? 

Would you expect that a cross between a race 
horse and some family dobbin would produce a 
line of racers? 

Separate your good corn from your poor, and 
keep it by itself, and you will find that it does 
not "run out," but even gradually, by careful 
selection, improves each season. 

Every farmer knows that corn must be 
planted in large quantities close together that 
a single kernel of corn, planted in one corner of 
a lot, apart from other growing corn, would be 
nonproductive. 

Yet how many of those who depend upon 
corn for their living fully realize the reason 
for this? 

The dianthus, with its nectar, its fragrance, 
its color, and its structural arrangement, has 
built up a partnership with the bee to perform 
its pollination; while corn, with no advertise- 
ment, no honey, no brilliant reds, no fragrance, 
has developed an equally effective plan of 



134 LUTHER BURBANK 

making the breezes act as its messenger of 
reproduction. 

Here is a plant, tall and supple, that responds 
with graceful movements to the wind. At its 
top it holds a bunch of pollen-laden tassels 
swaying tassels which, with each backward and 
forward movement, discharge their tiny pollen 
grains in clouds, which slowly settle toward the 
ground. 

Below, on the stalk of the plant, are the ears 
of corn, containing row after row of egg kernels, 
needing but combination with pollen grains from 
above to become, each, a seed capable of starting 
another corn plant on its life. 

Just as the eggs of the dianthus were housed 
in a protective covering, so the corn eggs are 
sheathed within protective husks. And just as a 
tiny stalk protruded from the egg chamber of 
the dianthus, so does the long silk which pro- 
trudes from the end of the husk serve the same 
purpose for the corn seed. 

Remove the husks from an ear of corn, and it 
will be seen that each strand of the protruding 
silk goes back to one individual kernel on the ear. 
That, between the rows of kernels, like electric 
wires in a conduit, each strand of the common 
bundle of silk protruding leads back to its sep- 
arate starting point. 



INGENUITY IN VARIATION 135 

To combine the characters of two parent corn 
plants, all that is necessary is to dust the pollen 
from the tassel of one on the silken ducts of the 
ear of another. 

And the breezes, as they swish a waving field 
of corn gracefully to and fro as they play 
through a forest of pines, or as they ripple the 
grasses of our lawns are performing their 
function in the scheme of reproduction as effec- 
tively as the bee does when it goes from dianthus 
to dianthus in search of sweets. 

Consider the simple salt-water cell, as seen re- 
producing itself under the microscope merely 
by splitting in two ; and those two each becoming 
two, and so on, endlessly. 

Observe that, with only a single line of parent- 
age from which to draw tendencies, the individ- 
uals to be found in this, the lowest form of life 
we know, are molded wholly by the variation in 
its temperature, or those other limited changes 
within a short-lived environment. 

And then consider the dianthus, the arum and 
the orchid with a thousand added complica- 
tions in their lives brought about by a single 
dominant purpose a thousand self-imposed dif- 
ficulties and obstacles which would be needless 
except for that guiding desire to give the off- 
spring a better chance than the parent had! 



THE COCONUT'S THREE 
EYES 

The coconut, as everyone knows, has 
a very hard shell, this protection cover- 
ing the whole nut except at one end 
where there are three unprotected 
"eyes" From one of these, when the 
nut sprouts to make a new plant, a 
strong root emerges, and a mass of 
roots is soon produced within the 
excelsiorlike covering, but inside the 
waterproof cover of the nut, which, for 
the purpose of illustration, has been re- 
moved. When the nut finds the proper 
environment, the roots burst forth and 
'grow rapidly. A tall stalk soon ap- 
pears, which finally becomes the trunk 
of the new palm. 



INGENUITY IN VARIATION 139 

We do not have to go to the tropics for evi- 
dences like these. 

There is probably no more familiar weed in* 
our vacant lots than the common dandelion 
( Taraxacum ) . 

Who can forget its feathery seed ball waiting 
when ripe for the first youngster, or the first 
draft of air to blow it away on its long sail 
through the air as it distributes its seeds some 
on stones, perhaps, and some on plowed 
ground, or in our lawns where it becomes a 
pest such a multitude of seeds that, though 
many be lost, some will find themselves throw- 
ing roots into new soil starting life in a new 
environment. 

Or we might learn a lesson from one of the 
wild chicories (Cichorium) which provides some 
of its seeds with wings to fly, while others it 
leaves wingless. Those seeds without wings fall 
at the feet of the parent plant as if to keep green 
the old family home; while those with wings fly 
away to start new families, under new condi- 
tions, where patent traits and tendencies 
latent elements of weakness or strength may 
cooperate to produce a chicory better adapted 
to its new environment. 

Or from that joy of childhood, the squirting 
cucumber (Ecballium) which, when ripe, fires its 



THE DEVIL'S-CLAW I 

As it grows in the tropics, or in our 
gardens, the seed pod of the devil 3 s-claw, 
or martynia, shown here, resembles a 
gourd in color and in texture of its 
covering. The succeeding prints show 
how it transforms itself to bite and hold 
on to passing animals with a bulldog 
grip. The young fruits are sometimes 
used for pickling. 



INGENUITY IN VARIATION 141 

seeds with such force that they are sometimes 
carried a distance of twelve to fifteen feet. 

Or even the sweet peas, or our garden pea, 
which when their pods have dried, have the abil- 
ity to throw the seeds some distance from the 
parent plant. 

In Mexico there is the familiar bronco or 
jumping bean, belonging to the spurge family, 
which calls in an insect to aid in the distribution 
of its seeds. 

While these beans are still green, they are 
visited by a moth which lays her eggs in them. 
As they ripen, the grub hatches out and lives 
upon a part of the food stored within. 

As if in partnership with the moth, the jump- 
ing bean tree has provided food for her off- 
spring, so that the larva has plenty to eat with- 
out injuring the seed within the bean. 

And the grub, as it hollows out the bean and 
jumps about within it, causes it to turn and roll 
rolls it into a new environment repays its 
family debt to the tree which gave it food. 

The devil's-claw (Martynia) has developed a 
curious power to bite and cling with bulldoglike 
grip, in its scheme of providing new environ- 
ments for its young. 

This spreading tropical plant requires consid- 
erable room to perfect its growth, grov^ng low 



THE DEVIL'S-CLAW II 

Martynia seed pod in the act of shed- 
ding its outside covering, leaving the 
sharp claws ready for business. 



INGENUITY IN VARIATION 143 

an the ground among other vegetation where the 
distribution of seed becomes a problem, grows a 
seed pod of seven inches or more in length. 

Its seed pod, while maturing, is incased in a 
pulpy covering with a thick green skin, and its 
bulb and hook suggest some kind of gourd. 

When the seeds within are mature, the outside 
covering splits and peels away, disclosing a seed 
nest which is armored with spines as thickly as 
a prickly pear. That which, during its early 
stages, formed the hook, now spreads into two 
branches with pointed ends as sharp as needles. 

Between these four-inch hooks, where they 
join the spiny bulb behind them, there appears 
a hole from which the seeds, if loosened from 
their former pulpy support, may, by pounding 
and thumping, find their way one by one out into 
the world. 

As the seed pod lies on the ground, its sharp 
hooks coiled in exactly the right position, it 
awaits a passing animal. This spring trap may 
remain set for many months, but once an animal, 
large or small, steps between those fishhook 
points, their mission is with great certainty ac- 
complished. The first slight kick or struggle to 
get away, imbeds them more deeply, and at each 
succeeding struggle the hooks bite in, and in, 
until finally the animal starts to kick and run. 



THE DEVIL'S-CLAW III 

Having completely shed its gourd- 
like covering, and with its jaws set for 
a passing animal, it will be seen that 
the pod itself is covered with prickly 
spines. When the fishhook points of 
the prongs bite into the leg of an ani- 
mal, the whole contrivance becomes 
balanced from these points, and at each 
jolt and jounce the heavier body of the 
pod pounds down upon the leg, its 
spines causing great pain. There is a 
small opening between the two prongs 
at the upper end of the pod itself from 
which the seeds come out, one at a time, 
at every bounce. When these are scat- 
tered over a mile or two of new en- 
vironment, the pod has performed its 
appointed mission. 



INGENUITY IN VARIATION 145 

Swinging to a leg or tail, suspended by the 
two sharp points of its prongs, the spiny hous- 
ing of the seed pod now comes into play. At 
each bound or jump, the pod flops up and down 
and its prickly points, adding to the pain of the 
ever-pinching hooks, are sure to keep the animal 
in motion. As the frightened beast makes haste 
to get away from an enemy which it cannot see, 
the seeds within the pod are shaken one by one 
through the narrow opening, falling on the 
ground. 

The sailor is awed by the mountains, and the 
mountaineer is awed by the sea. 

And we, too, are more apt to wonder at the 
jumping beans of Mexico and at the devil's-claw 
of the tropics than at the cherry tree in our own 
back yard which outdoes both of these by 
forming a double partnership. 

Just as the dianthus bids for the bees, so the 
cherry blossom, with its delicate pink and its 
offering of fragrance and honey, advertises for 
butterflies and bees to bring the pollen from 
some neighboring tree. 

And this partnership concluded, the accounts 
balanced, and the books closed, it then seeks new 
partners in the birds. 

That delicious meat around the seed, that shiny 
skin of red, and that odor of the cherry as it 



146 LUTHER BURBANK 

ripens these are a part of the advertisement to 
the birds or animals a lure to get them to eat 
the fruit and carry the seed as far away as they 
may to another a new environment. 

Shall we wonder at the jumping bean and the 
devil's-claw when our own cherry tree is getting 
the bees to give its offspring new heredities and 
the birds to surround these heredities with new 
environments in which to grow? 

Wherever we look we see a new display of 
ingenuity all for the sake of variation varia- 
tion which may mean retrogression as well as 
advancement but such infinite variation that, 
surely, there can be found one out of a thousand, 
or one out of ten thousand, or one out of a mil- 
lion better adapted than those that went before. 

Every flower that delights our eye, and every 
fruit which pleases our palate, and every plant 
which yields us a useful substance, is as delight- 
ful as it is, or as pleasing or as useful as it is, 
simply because of the improvement which has 
been made possible through variation. 



No two living things are exactly 
alike. 



THE RIVALRY OF PLANTS 
TO PLEASE US 

ON THE FORWARD MARCH OF 
ADAPTATION 

"" 1C TE cut our alfalfa four, or five times 

y y each season," says some one, "why 

doesn't it grow spines to protect itself? 

.We destroy our lettuce before it goes to seed; 

why doesn't it develop a protective bitterness 

like the sagebrush? 

"We rob our apple trees of all their fruit the 
moment they are ripe; why do they not become 
poisonous like the desert euphorbias?" 

As we have taken the cactus as an example, let 
us go back to it and read the answer. 

Grim and threatening though the cactus 
seems, it is not without its softer side; in the 
springtime its blossoms, a multitude of them, 
push their way through the spiny armor and 
rival the rose in beauty of form and color, even 
competing with the orchid in the delicacy of their 
hues. 

147 



148 LUTHER BURBANK 

No favorite garden flower can outdo this 
ungainly monster of the desert, when in bloom, 
in the seductiveness of its advertisements put 
forth to attract insects. 

When summer comes, and the insects have 
paid, by the services rendered, for the honey 
taken, the nest of fertile eggs beneath each 
cactus blossom begins to grow into a more or less 
luscious fruit. 

In this cactus fruit there is a sweetness which 
makes the fruit as tempting as that of the straw- 
berry, raspberry, banana, or orange. Its outer 
covering, in some of the improved varieties, is as 
beautiful and varied as that of the apple or the 
peach. 

Thus, in the springtime, the cactus, like the 
cherry, advertises to the friendly insects to bring 
its offspring new heredities, and in the fall it 
advertises to the friendly birds to carry off its 
seed and plant it where its young may have the 
advantages of new environment. 

In its brilliant flowers and tempting fruit we 
read its receptiveness to the friendship of the 
birds and bees. 

Those spines and flowers and fruits tell us 
that, while its ancestors were fighting a common 
foe, they still found time to build up lasting part- 
nerships. 



RIVALRY OF PLANTS 149 

And so, with every plant that grows, we shall 
see these same tendencies instincts shall we call 
them? to ward off the enemy and make use of 
the friend. 

So long as plants grow wild, the frosts, the 
winds, the hailstorms, the droughts, and the ani- 
mals are principal among the enemies with which 
they have to reckon. 

So long as they grow in the woods, or 
on the mountains, or in the deserts, the bees 
and the birds and the butterflies the warmth 
of the sun and moisture and fertility of the soil 
these are among the friendly factors in 
their lives. 

But when we take plants under cultivation, 
we upset their whole environment. 

We build fences around our blackberries so 
that they need no thorns. We save the seeds of 
our radishes, and the bulbs of our lilies, and 
through human organization distribute them and 
plant them wherever they will grow. We cut 
grafts from our apple trees and ship them from 
county to county, and State to State, and nation 
to nation, and zone to zone. We select, and im- 
prove, and plow, and harrow the ground for our 
plants; we water them when they are dry; we 
surround them with shade trees if they need 
shade, we cut down the shade trees if they prefer 



150 LUTHER BURBANK 

the sun; we plant their baby seedlings under 
glass, and give them every favoring condition in 
which to mature; we remove what for ages have 
been the chief problems of their lives we take 
over their two prime burdens, the burdens of 
self-defense and reproduction. 

The frosts, and the winds, and the hailstorms, 
and the droughts, and the animals are no longer 
the chief enemies of plants; for man, when he 
comes into their environment, is more dreadful 
than all of these combined if he chooses to 
destroy. 

And the bees and the birds and the butterflies, 
and the warmth of the sun, and the moisture in 
the soil, fade into insignificance as friendly in- 
fluences when compared with that of man if it 
pleases him to be a friend. 

So the cherry tree and dianthus still advertise 
to the bees and birds, as of old. 

But their main advertisement, now, is an ad- 
vertisement to us; their strongest effort, now 
that we have become predominant in their lives, 
is to lure with their blossoms and their fruit to 
enchant us with their odors, and colors, and lus- 
ciousness, as they formerly enchanted only the 
bees to win and hold our appreciation and 
aff ection, and merit our kindly attention and 
care. 



RIVALRY OF PLANTS 151 

Our alfalfa, lettuce, and apples, like our 
horses, our cows, our dogs, have found in man 
a friend stronger than the strongest of their 
enemies. 

So their welfare now is measured by the use- 
fulness of service they can render in repayment 
for man's care. 

There is a common snowball in my yard which 
advertises alone to me. 

In the woods around there are other snow- 
balls of the same family wild snowballs into 
whose life history man, as a part of environment, 
has never come, except perhaps to destroy. 

The wild snowball, with only a fringe of blos- 
soms, and a mass of egg nests and pollen inside 
the fringe, is still advertising to the bee. 

But the snowball in my yard has responded to 
my care and the care of those who went before 
me, till its stamens and pistils, as if seeing their 
needlessness, have turned to petals till its eggs 
have grown sterile, even should an insect come. 

And so, with every snowball which is grown 
for the beauty of its flowers cultivation has re- 
lieved it of the need for reproduction, and what 
once was but a fringe of flowers has been trans- 
formed into a solid mass of blossoms. 

Just as a mother cat can make a dumb appeal 
for the protection or the sustenance of her 



THE SNOWBALL CULTI- 
VATED AND WILD 

The upper cluster of flowers is the 
one which is grown for its ball of white 
flowers. The snowball flowers below 
are wild, such as grow in the woods. 
The wild snowball, it will be seen, uses 
the flowers to attract messengers of 
pollination to the reproductive mecha- 
nism which the outside flowers encircle. 
The upper snowball, however, has lost 
its power of reproduction by seed, and 
advertises to us, instead, to perpetuate 
its race. 



RIVALRY OF PLANTS 153 

kittens, an appeal no human being can misun- 
derstand, just as strongly and just as clearly do 
the snowballs, by the beauty and helplessness of 
their self-sterilized flowers, appeal to us to see 
to their protection and effect the perpetuation of 
their kind. 

Many violets, as they grow wild in the woods, 
bear two kinds of blossoms. 

One is the flower, rich in color and often 
in fragrance, which is borne at the top of 
the plant. 

The other, an egg nest without petals, odor, or 
beauty, or other advertisement which is borne 
near the base of the plant. 

The flower at the top, like the flower of a 
geranium, advertises to the insects to bring 
pollen from other plants. 

The flowerless egg nest below needs no insect 
to bring it pollen it pollinates itself and pro- 
duces fertile eggs with only a single strain of 
heredity; this through necessity and not to the 
best interest of the heredity of the plant, though 
these are fertile seeds. 

Some of these violets with upper and lower 
blossoms, particularly those which grow in the 
shade, never open their upper flowers as if 
knowing that the friendly insects so prefer the 
sun that no attempt at advertisement could lure 



154 LUTHER BURBANK 

them to the shade. These violets reproduce 
themselves wholly by the self-fertilization which 
goes on within the colorless flower below. 

And there are violets of the same kind, 
blooming in the sunlight, which open their 
upper flowers so that, if visited by insects, 
the seed w r ithin matures; but, as if in doubt 
i of the effectiveness of their advertisement, the 
lower blossoms continue to produce their in- 
bred seed. 

And there are still other violets Which, as if 
assured of the friendship of the insects, have 
ceased to make the colorless blossoms below, and 
produce their entire output of seed at the base of 
the brilliant upper flower. 

Here, in these three kinds of violets, is written 
the story of a plant's struggle with wild environ- 
ment in which man has not yet become a factor; 
the story of an unequal struggle in which the 
stages of failure, partial victory, and complete 
triumph are clearly laid before us. 

Into the life of the violet, some few hundred 
years ago, there came a new element of environ- 
ment man. 

A single violet plant which was taken from its 
icatch-as-catch-can existence, let us say, found it- 
self in fine-combed soil in a shady place in some 
one's dooryard. 



RIVALRY OF PLANTS 155 

If it rained too much, drainage took up the 
excess. When the rains did not come, the soil 
was sprinkled. 

Under cultivation and kindly care the dis- 
couragements of its life grew less and less, and 
the encouragements to thrive grew more and 
more. 

Soon this violet, as if assured of reproduction, 
abandoned the blossoms at its base, and threw its 
energies into making bigger and brighter and 
more beautiful blossoms at its top. Where it 
had half-heartedly advertised to the bees of old, 
it now concentrated its efforts to win the ap- 
proval of the new-found friend whose dooryard 
brought it opportunity. 

And this is the life story of the violet which we 
now call the pansy. 

On the one hand, in the woods, we see its wild 
kinfolk still struggling against unequal odds; on 
the other we see its own large, beautiful pansy 
petals, and the increased brilliancy of its hues; 
each a response to environment. 

Truly, in the pretty face of the pansy 
we may read the vivid story of man's impor- 
tance as a friendly element in the lives of 
plants. 

Where do the flowers get their colors? 

From the bees, the birds, and from us. 



156 LUTHER BURBANK 

On the experiment farm at Sebastopol there 
grow two ordinary-looking pear trees which am- 
plify the thought. 

One of these trees produces abundantly aro- 
matic, luscious, easily digested pears a delight 
to the eye and to the palate. 

The other produces hard but juicy pears which 
never become mellow and uncooked are as indi- 
gestible as the quince before I commenced its 
improvement. 

Looking at these trees side by side, it would be 
difficult for the common observer to realize that 
their fruit could be so different. In their fruit 
alone do they differ. 

Since these two pear trees illustrate an impor- 
tant point, let us begin at the beginning: 

It was in Eurasia, some two thousand years 
ago, that man first perhaps realized that the pear 
fruit was good to eat. 

Coming to us, then, out of the obscurity, the 
pear, during these twenty centuries, has spread 
to the east and to the west, until it has com- 
pletely encircled the globe a slow process, but 
one which takes place in every desirable fruit 
which is discovered or produced. 

As Europe became more and more settled, the 
pear kept pace with the invaders. It followed 
them to the British Isles, it followed them across 



RIVALRY OF PLANTS 157 

the Atlantic to America. It followed them west- 
ward across this continent as the pioneers pushed 
their way to the Pacific. 

In the same way it worked its eastward jour- 
ney through Siberia, and China, and Japan 
more slowly, perhaps, than under the influence 
of European and American hurry and enter- 
prise, but just as constantly, and just as surely 
till now, in friendly climates, it is a world-wide 
fruit. 

Both of the pear trees described here, as in 
fact all of the pear trees which we know to-day, 
seem to have come from those common parents 
in eastern Europe or western Asia. 

The one which bears the luscious fruit is the 
Bartlett pear an excellent though common 
variety in the United States. 

The other, with its bitter, indigestible fruit, is 
one which was imported from China. \ 

The lesson which these two pear trees teach is 
that fruits, like flowers in their rivalry to please 
us, adapt themselves to the tastes, desires, and 
ideals of the human neighbors among whom they 
grow. 

Here, in America, we like fruits that are soft, 
large, sweet, luscious, juicy, aromatic, easy to 
digest when eaten raw. Our pears grow that 
way. 



158 LUTHER BURBANK 

In Japan and China they like fruits which are 
hard but juicy, suitable for pickling, preserving 
or- cooking. The Chinese and Japanese pear 
trees bear that kind of fruit. 

Neither the Oriental pear, nor our American 
type is like the original wild parent which was 
first discovered in Eurasia. 

Each has changed one toward one set of 
ideals and the other toward another set. 

If we could lay bare before us the whole his- 
tory of the pear tree if we could picture in our 
minds its stages of progress beginning back in 
the old times, say, when instead of a fruit it 
bore only a seed pod like the wild rose we 
should see a record of endless change, constant 
adaptation. 

We should see that soil, moisture, sunshine, 
and air, throughout the ages, with the aid of 
fruit-loving animals and man, have all played 
their parts in gradually transforming the pear 
tree into its present state. 

We should see that other plants, crowding it 
for room or sapping the moisture from around it 
cr adding fertility to the soil by their decaying 
leaves, have done their share in hastening its im- 
provement. 

We should see that the bees and butterflies 
and birds with their help, and the caterpillars, 



RIVALRY OF PLANTS 159 

locusts, and deer in their apparent destructive- 
ness, have all served to aid the onward march. 

We should see all the while a steady change 
for the better sturdier pear trees, brighter blos- 
soms, more seed, better fruit. 

We should see that, with the aid of the ele- 
ments, the pear tree adapted itself to exist, hard- 
ened itself to withstand many soils and many 
weathers. 

We should see that, with the unintended aid of 
its plant and animal enemies, it gained strength 
through overcoming them. 

We should see that, through the bees, it was 
helped into variation by combining heredities; 
and by the birds and animals it was helped into 
still further variation by wider distribution of its 
seeds. 

Then, overshadowing all of these influences 
there came into its life new influences of man 
man savage and civilized, Oriental and Occi- 
dental man with a liking for pears. 

In Europe and here in America, we who have 
grown pears have cultivated the trees which bore 
the largest, tenderest and most delicious pears 
because those were the ones we liked best. 

When we have bought pear trees to plant in 
our orchards and gardens, we have chosen those 
which would give us the kind of fruit we prefer. 



160 LUTHER BURBANK 

The pear trees which have pleased us have re- 
ceived our care and cultivation and we have 
multiplied them. The pear trees which have 
failed to produce fruit up to our ideals we 
have neglected and allowed to die so that 
they have practically disappeared from our 
orchards. 

The Orientals, their tastes running in opposite 
directions from ours, have ignored pear trees 
which bore the kind of fruit we prefer, and have 
selected, and saved, and fostered, and propa- 
gated those which gave them the hard cooking 
and pickling fruit of their ideals. 

And so the struggle for adaptation set in mo- 
tion by the soil, the warmth, cold, moisture, and 
the winds, was supplemented by the bees, and 
then by the birds and other animals, until now we 
can read in the result our own influence and that 
of the Orientals. 

There are differences between our dress and 
the dress of the Orientals; between our religions 
and the religions of the Orientals; between our 
ambitions and the Oriental ambitions; between 
our architecture and the architecture of the 
Orient all reflecting the national or racial dif- 
ferences between the ideals of the two peoples. 

And just as surely as the ideals of a people 
influence the architecture and the literature with 



RIVALRY OF PLANTS 161 

which they surround themselves, just as surely 
as they change ambitions, mold religions and 
adapt clothing to their conditions; just so surely 
do they influence and change the characteristics 
of the plants in whose environment they live. 

When I say that man is the most important 
element in the environment of plants, I do not 
mean those few men who devoted their lives to 
the improvement of plants. I do not mean the 
botanist, the horticulturist, the florist, the seeds- 
man, the nurseryman, the agricultural experi- 
mentalist. I mean man in the mass man busy 
with his dry goods store, or his steel company, 
occupied with his law, or his medicine, weary 
from his daily blacksmithing, or his carpenter- 
ing. I mean just man, the neighbor of plants, 
whether he be their friend or their enemy who- 
ever he may be. 

It was the Indian who gave us, here in Amer- 
ica, the most important crop we have. 

It was the primitive races in America who 
adopted one of the wild grasses and finally pro- 
duced our maize ; which, however, when America 
was discovered, was primitive in comparison to 
the wonderful varieties which have since been 
developed. 

Or, to turn about, it was the desire of the 
Indian for a food plant like this that led the 

Vol. 1 Bur. F 



SOME FORMS OF CORN 

In the direct-color photograph print 
shown here the central ear is one form 
of the "pod" corn, in which each kernel 
is incased in a separate sheath. The ear 
at the left is another form of teosinte 
with larger kernels than those in the 
preceding print; from this latter the 
process by which the kernels crowded 
each other until the cob increased in size 
may be readily imagined. The ear 
shown at the right is an improved pop- 
ping corn. 



RIVALRY OF PLANTS 163 

Euchlcena, or teosinte, by gradual adaptation, to 
produce Indian corn or maize. 

On one of my experiment farms there grows, 
to-day, this same Euchlcena which the Indians 
found. 

It bears tiny ears with two steel-armored rows 
of barleylike kernels on a central rachis not as 
large or as strong as the central stalk of a head 
of wheat. 

And when the prehistoric and more modern 
races came into its environment it responded to 
their influence as the pansy responded to care 
and cultivation in its new man-protected home. 

Where teosinte had formerly relied upon its 
own resources to find a suitable soil for its seed, 
it found in the Indian a friend who crudely but 
effectively scratched the soil and doubled the 
chance for its baby plants to grow. 

Where it had been choked by plant enemies, 
and starved for air and sunlight by weeds, it 
found in the Indian a friend who cut down and 
kept at bay its competitors. 

Where it had been often destroyed by the 
animals before its maturity, it found the selfish 
protection of the ancient races as grateful as 
though it had been inspired by altruism. 

Planted in patches instead of straggling here 
and there as best it could before, this sturdy grass 



164 LUTHER BURBANK 

found its reproduction problem made easier 
through the multitude of pollen grains now float- 
ing through the air. 

And so, by slow degrees, it responded to its 
new environment by bearing more and larger 
seeds. 

As the seed kernels increased in numbers and 
in size, the supporting coblet which bore them 
grew in sturdiness and length. 

From two, the rows of kernels increased to 
four, six, eight, twelve, and now, in some varie- 
ties, to forty or more. 

Here again the selfish motives of the primitive 
races served to help the plant in its adaptation as 
naturally the largest and best developed ears 
would be saved by some one. 

So, under cultivation, the wild grass through 
adaptation was transformed into Indian corn. 

There were two wealthy men in England who 
took up the daffodil and narcissus, growing end- 
less quantities of seedlings for amusement. 

Both of these men, so it happened, were bank- 
ers. One was a rather large, coarse, strong, 
dominating type of man not a repulsive man 
by any means, but lacking a little in refinement 
and the more delicate sensibilities. 

The other banker was a highly sensitive, nerv- 
ous, shrinking man with a great eye for detail, 



RIVALRY OF PLANTS 165 

a true appreciation of values, a man who looked 
beneath the surface of things and saw beauty in 
hidden truths, a man who thought much and said 
little. 

These men were rivals in their daffodil and 
narcissus-growing pastime, and each of them 
succeeded in producing some wonderful vari- 
ations and adaptations in their plants. 

When these bankers died, their daffodil and 
narcissus bulbs were offered for sale and fell into 
the hands of a friend of mine, Peter Barr, a great 
bulb expert of England. 

Peter Barr told me that though the bulbs 
bought from those two estates were mixed and 
planted indiscriminately on his proving grounds, 
he could go through a field of those daffodils and 
narcissus and, simply by the blossoms, tell which 
had come from one estate and which from the 
other. 

The flowers that came from the bulbs that 
represented the work of the first mentioned 
banker were large, strong, coarse, brightly 
colored flowers with a beauty that called to 
the passer-by as loud as if with words, and a self- 
reliant attitude as if bespeaking an ample ability 
to take care of themselves. 

And the flowers which came from the bulbs 
produced by the second mentioned grower were 



VARIATION IN CORN 
SEED 

Material has been found for most of 
the corn experiments in variations as 
to one quality or another that appear 
among plants of the same species. It 
may or may not be necessary to accen- 
tuate variation by hybridizing experi- 
ments. The range of variation that 
may be shown in the seed of a single 
species is illustrated in this lot of ker- 
nels of corn, which show surprising 
diversity in shape, size, and color. Num- 
berless new varieties could be developed 
through selective breeding from such a 
lot of seed as this, not only as to form, 
size, and color, but in productiveness, 
quality, and every other desirable 
character. 



RIVALRY OF PLANTS 167 

charmingly delicate unobtrusively artistic not 
loud in color, but gently alluring. 

It costs money to ship oranges, so the more 
the meat and the less the rind, the less we waste 
in transportation charges. 

A comparison of the wild orange with the 
cultivated fruit of our orange groves shows how 
this fruit has adapted itself to our ideas of 
economy. 

Lettuce in the head makes a more appetizing 
salad than lettuce in large, sprawling leaves. 

A comparison between wild lettuce and the 
head lettuce on our green grocer's stand shows 
plant adaptation in a most wonderful way to our 
tastes. 

And so with celery, and artichokes and every 
plant that is grown for the market wild, its 
adaptations are toward meeting wild environ- 
ments; cultivated, its adaptations are selected 
toward fitting itself into our routine of life. 

We have seen the price which variation costs; 
now we begin to see the value of it. Among 
those violets, environment the environment of 
the present combining with heredity which is the 
recorded environment of all the past contrived 
to see that there were no duplicates; that each 
violet, a little different from its mate, might, 
through its difference, be suited to a separate 



168 LUTHER BURBANK 

purpose, or fitted to carry a separate burden, or 
designed to fill a separate want. 

If the violets had been as like as pins, they 
would have stayed as like as pins when planted 
in that friendly dooryard. 

But because each had within it the power of 
transmitting variation, the power of responding, 
ever so little, to the trend of its surroundings, 
one violet became a pansy. 

Among our human acquaintances we know 
those who are sturdy, and those who are weak; 
those who have well-developed minds at the 
expense of their muscles, and those who have 
well-developed muscles at the expense of their 
minds, and those with a more evenly balanced 
development; we know some who are tall and 
some who are short; some with brown eyes and 
some with blue; some who lean toward com- 
merce, and some who lean toward art; and on 
and on, throughout an infinite number of vari- 
ations, an infinite combination of these vari- 
ations, each variation representing the result of 
present environment reacting upon all the envi- 
ronments of the ages, stored away. 

As a people, we traveled by stage till the 
railroad came; and then in a single generation, 
because of the variation and the adaptability 
among us, we found surveyors to push their 



RIVALRY OF PLANTS 169 

transits over the hills, and valleys, and streams; 
we found woodchoppers to make ties, we found 
steel makers who for the first time in their lives 
fashioned a rail, we found engineers, and fire- 
men, and switchmen and superintendents, and 
railroad presidents, each to play his part in ful- 
filling the great common desire for transporta- 
tion, each able to adapt himself to new duties 
and all because of this acquired variation that is 
within us. 

As a people, we submitted to a ruler across the 
seas till among our variant individuals there 
arose some who, different from the rest, adapted 
themselves to the formulation of a declaration of 
independence, the framing of a code of prin- 
ciples, the organization of a successful revolution. 

As a people, threatened with the constant peril 
of cures which were worse than their diseases, 
there appeared out of the variable mass one who 
gave us antiseptic surgery. 

Where are those who, a century ago, said 
that railroads could never be? Where are 
the Tories of revolutionary times? And where 
are those barbers of ancient days with their 
cupping glasses and their lancets and their 
leeches? 

Ah, where are the pear trees of Eurasia that 
failed to fit into the scheme of adaptation where 



RAINBOW CORN 

In previous chapters of this volume 
there have been shown several direct- 
color photograph prints bearing on the 
evolution of corn. The plant shown 
here is still another variation, grown 
only for ornamental purposes, which 
has been brought about. As can be 
seen from the print,, the leaves take on 
the brilliant colors of the spectrum 
bright reds, yellows, and purples inter- 
mingling with the green. For decora- 
tive purposes rainbow corn is a great 
success. 



RIVALRY OF PLANTS 171 

are the dianthus plants that did not learn to 
advertise to the bee and where are the desert 
cactus plants that could not protect themselves 
with thorns? 

On and on we go, one step backward some- 
times, then two steps forward marking time 
awhile, then onward with a spurt the pear tree, 
the dianthus, the cactus plants, and we each 
individual among us a little different from the 
rest, each with a separate combination of old 
environment stored within us, finding always 
an infinity of new environment to bring it out; 
growing up together, the pear trees, the dian- 
thus, the cactus plants and we, all of us depend- 
ing on the others, and each of us playing his 
separate part in the march of adaptation. 

On and on we go, because of Infinite Vari- 
ation. 

And so, from whatever viewpoint we approach 
the study of plants whether with an eager eye 
to the future and the past, or whether with an 
eye, opened only a slit, to see simply the things 
we can touch and feel, we find evidences of adap- 
tation made possible through variation. 

The violet, responding to kindness, became a 
pansy. 

The pear, responding to racial tastes, adapted 
itself to the Orientals and to us. 



172 LUTHER BURBANK 

Corn, responding to a need for food, produced 
forty times the kernels which it had produced 
before. 

The orange, the lettuce, the celery, and every 
cultivated plant that grows, responding to our 
market demands, have transformed themselves to 
meet a readier sale. 

And those daffodil and narcissus seedlings, 
how eloquently they tell of the adaptation of a 
plant to fit an individual ideal! 

We studied electricity a long time with- 
out much apparent practical benefit. Then 
suddenly electric lights and trolley cars were 
everywhere. 

We knew the principles of sound vibration for 
centuries before the telephone and the phono- 
graph appeared, but it took less than a genera- 
tion to make them universal. 

We dreamed motor carriages three hundred 
years before we got one, and then, in a decade, 
we awoke to find our dream come true. 

And, almost from the beginning, man has 
studied the forces which go into the make-up 
of life without much encouragement, till now 
these ages of contemplation have begun to 
crystallize into thornless cacti, stoneless plums, 
fragrant calla lilies and a thousand other 
results as definite and perhaps even more 



RIVALRY OF PLANTS 173 

fundamentally important to the life and well- 
being of the human race than the trolley 
or the telephone or the omnipresent auto- 
mobile. 

Who among us shall say what new plants even 
a decade now may bring forth? 



On and on we go; one step back- 
ward, sometimes; then two steps 
forward; marking time awhile; 
then onward with a flight. 



LET US NOW PRODUCE SOME 
NEW COLORS IN FLOWERS 

DEVELOPING DESIRED CHARACTERS 
IN HEREDITY 

AN architect, in selecting the materials for his 

A% structure, sends for limestone to Bedford, 

Indiana, or for marble to Carrara, Italy, 

or for bricks to Haverstraw, N. Y., or for rustic 

redwood to California. 

In the process ol -turning his blue print into a 
building, he draws on the whole world a little 
here and a little there for his supplies. 

So, in the production of a new plant in which 
w r e hope to produce some definite useful results, 
we must first seek out the materials with which to 
build. 

Only our search will be, not for substance, but 
a search for stored-up heredities not a search 
for bricks or stone or lumber, but a search for 
living traits. 

The sturdy dandelions in our vacant lots, with 
their parachutelike seed balls, reveal a structural 

175 



CALIFORNIA POPPY 

(Eschscholtzia) 

This direct-color photograph print 
shows the wild California poppy, so 
called., golden-yellow, as it grows in this 
vicinity. This common wild flower 
covers California's hills and valleys at 
certain seasons and from it the State 
is supposed to have received its name 
"The Land of Fire." 



DEVELOPING CHARACTERS 177 

ingenuity and fitness to survive which may 
have cost ten thousand generations of patient 
struggle. 

The sweetness of our cherries, our grapes, our 
plums, has been developed only through ages 
and ages of response to environment, with some 
environments so oft repeated that they h*. e 
hardened into heredity. 

The flowers on our lawns may have acquired 
their colors in France, or in Ecuador, or in Si- 
beria; our nuts reflect flavors acquired through 
a world- wide migration; and even our early 
vegetables show traits which hark back to 
times before animals and men came into 
their lives. 

So, just as the earth has stored up limestone 
in Indiana, and marble in Italy, and brick-clay in 
New York, and five-thousand-year-old redwoods 
in California, for the architect to draw upon, just 
so, in a world full of plants, representing an 
infinity of ancestry with its infinity of heredity, 
will we find an infinity of traits with which to 
build. 

If we wish to change the color of a flower, or 
its fragrance, its size, or its adaptability to 
climate if we have it in mind to transform a tree 
or its fruit, or to give any plant a new trait or a 
new habit the most practical way is to accumu- 



178 LUTHER BURBANK 

late and intensify the quality we want out of the 
mass of heredity about us. 

"I thought," says some one, "that plants could 
he transformed merely by changing the environ- 
ments in which they grow." 

So they can, if time is no object. But the 
quick and economical way is to take advantage 
of the combined environments of the past which 
are at our instant disposal; to short-cut to our 
result by using well-established traits and thor- 
oughly formed habits, rather than to spend the 
years or lifetimes which might be necessary to 
produce new traits and new habits from the be- 
ginning. 

It is better to seek out, first, what nature has 
stored away for us, and then to use new environ- 
ments to improve or intensify traits and habits 
which already have the advantage of several cen- 
turies of start. 

It is the same principle of economy which we 
apply to everything we do. 

So long as there is plenty of coal within easy 
reach it does not pay us to build machines to 
utilize the energy of the sun's rays or of the ocean 
tides. And, similarly, so long as there are un- 
told thousands of plants embodying, in some 
form, almost every conceivable trait we might 
desire untold thousands of plants like the cac- 



DEVELOPING CHARACTERS 179 

tus, crab apples, or wild potatoes waiting only 
our attention to make them useful we can hard- 
ly afford to waste time in doing what nature 
already, laboriously, has done. 

The hard part, always, is to make the start. 

Those who are late sleepers, for example, 
know the weeks of discouraging attempts it 
takes to fix the habit of arising at seven instead 
of eight, or at six instead of seven. Yet, once we 
have thoroughly accustomed ourselves to the new 
hour of awakening, it is just as difficult to get 
back to the old hour as it was to get away from it. 

It is as if the tendencies within us, having 
accommodated themselves to each other and to 
our surroundings, cling together tenaciously to 
maintain the equilibrium between themselves; 
when we change our surroundings they adjust 
themselves to the change with difficulty ; but once 
adjusted, hold together as firmly again as they 
held before. 

So in plant life; when we transplant a flower 
or a tree, it shows signs, in accommodating itself 
to its new surroundings, of evident distress; it 
looks sickly, its leaves droop, it gives many out- 
ward proofs of the inward struggle which it is 
undergoing. 

As soon, however, as its suddenly scattered 
tendencies have collected themselves, the plant 



A BURBANK BONFIRE 

The photograph print here is remark- 
able in that it is made from a color 
photograph taken at night of one of 
our so-called $10,000 bonfires. Such 
a photograph in even black and white 
would be extremely difficult of accom- 
plishment. 



DEVELOPING CHARACTERS 181 

begins an era of immediate improvement, and 
does as well or better than it did before trans- 
planting as well, in fact, as its new surround- 
ings will permit. 

If new habits are hard to start, new traits are 
harder. It is hard to teach a plant to twine 
when it has never twined before, or to per- 
suade it to be pink when it has always been 
yellow; just as it is hard to get a boy interested 
in the study of law when his likes, all his life, 
have been along the lines of engineering or 
mechanics. 

In the establishment of a new trait, in fact, the 
whole motion of life must be interrupted, its 
momentum arrested, the resulting Inertia over- 
come, and new momentum in a new direction 
gained. 

But, if every difficulty has its recompense, we 
are well repaid for the labor of acquiring or in- 
stilling a new trait by the fact that, once ac- 
quired, it has a tendency of Us own to increase 
and expand and grow. 

The boy who finally gets interested in law, 
who gets past the point where it becomes an irk- 
some drudgery, begins, at length, to develop a 
steadfast love for his work so that what was to 
him, once, a bugbear at last becomes an absorb- 
ing ideal. 



182 LUTHER BURBANK 

The cactus, for example, which produced its 
first spines with difficulty, later became more 
and more spiny, even though the need for spines 
had disappeared. Our flowers grow more beau- 
tiful, our fruits more luscious as their tendencies 
gain momentum. 

We may take it as a rule, almost, that a habit, 
once fixed, hardens : that a trait, once established, 
grows stronger and stronger. 

The easiest way, therefore, is to work with 
heredity, and not against it to spend a month 
searching out a desirable trait or habit, rather 
than to spend a year or a decade trying to over- 
come an undesirable one. 

And, now, to a practical experiment. 

From almost any seed house we may procure 
the seeds of two African wild flowers. One is the 
African orange daisy, the other a white daisy of 
the same family. 

The orange daisy is a sun-loving flower, as its 
beautiful, rich tint clearly testifies. 

The white daisy, by its whiteness, shows 
equally unmistakable evidence of an ancestry 
which has preferred the shade. 

Bright colored flowers are most invariably 
those which have grown in the sun. White 
flowers are more often those which bloom at 
night. 



DEVELOPING CHARACTERS 183 

"Because the sun reacts with the soil to pro- 
duce bright colors, while the shade does not?" I 
have been asked. 

I prefer to believe that insects make the colors. 
The flowers which grow in the bright light need 
their brilliance to attract the insects, flowers in 
the shade are more easily observed if they are 
light or white in color ; it is all a matter of adver- 
tising contrast; and, throughout the ages, each 
particular flower has been striving to perfect a 
color contrast scheme of its own. It may be that 
the combination of sun and soil makes possible 
brighter colors than the combination of shade 
and soil; but wind-loving plants, like corn and 
trees, which grow in the sun, do not bedeck them- 
selves in colors only the flowers which find it 
necessary to attract the insects. 

In practice, at any rate, the color of a flower 
is one of the reliable guides in the study of its 
life history. 

Taking the orange daisy and its white cousin 
side by side, we see at once a family resemblance. 

The leaf formation, the root formation, the ar- 
rangement and the number of rays, the ar- 
rangement of stamens and pistils, bespeak the 
fact that here are two plants more or less closely 
related ; one orange and one white ; the white one 
a little taller, more graceful perhaps, and slightly 



THE CALIFORNIA POPPY 
TURNED CRIMSON 

This beautiful variation was produced 
on my place some twenty-five years 
ago. Many new shades have been pro- 
duced here since then, among them one 
named ff Fire Flame" which is an un- 
usual and very pleasing combination 
of the colors yellow, orange, and 
crimson. 



DEVELOPING CHARACTERS 185 

less hardy; but cousins, beyond doubt, having 
within them many parallel strains of heredity. 

Let us assume, then, that the orange of the 
orange daisy is the heredity of ages of sunshine 
and the white of the other daisy is the inheritance 
of ages of shade; there are other indications in 
the habits of these plants to verify this conclu- 
sion ; that both started from the same point, and 
that one found itself growing in cleared fields, 
while around the other developed a forest of 
shade; so that, finally, as environment piled up 
on environment and accumulated Into heredity, 
each flower became so firmly fixed in its own 
characteristics as to constitute a species, as man 
has often chosen to call it, of its own. 

If we take the seeds of the African orange 
daisy, and plant them in the shade, they will still 
produce orange flowers. That is stored-up 
heredity. Xo doubt, if we continued, year after 
year, to replant them in the shade for a century 
or so, they would begin to transform themselves 
to white like the other daisy. 

If we plant the white African daisy in the sun- 
shine, it will still give us flowers of white the 
heredity of ages overbalancing the pull of im- 
mediate environment, and needing a long-con- 
tinued repetition of environment to balance and 
finally overcome it; but if we were to keep it in 



186 LUTHER BURBANK 

the sun throughout enough generations it would, 
no doubt, bear us flowers of brilliant orange. 

Here, then, are two divergent strains of hered- 
ity in two somewhat closely related species 
one orange, one white one sturdy, one fragile 
each strain so thoroughly fixed that in a lifetime 
it would probably be impossible, through en- 
vironment alone, to overthrow it. 

Let us next take a twenty-foot flower bed; di- 
vide it in the middle, plant one side solid with 
the orange daisies, and the other side solid with 
white daisies, and let the bees and the breezes 
combine those heredities to produce a perturba- 
tion, through which we hope to secure some new 
colors. 

The breezes and the bees carry the pollen from 
flower to flower; the rays fall away, and dis- 
close the fertile seed in which, for the first time, 
these two strains of heredities are combined. 

From the millions of seeds which we obtain 
from these composite flowers there are some with 
the white tendencies stored away unaltered, some 
with the orange tendencies still predominant- 
some with white pulling evenly against orange, 
some with orange slightly stronger than white, 
and all with an infinity of variation between. 

We shall find in some seeds a combination 
of tendencies, not only of the two species, 



DEVELOPING CHARACTERS 187 

but of the families of the two species, and 
of the individuals of those families: mixed, 
upset, disturbed so thoroughly that not only 
will the life history of both parents be laid 
bare in the resulting plants, but through the 
blends new characteristics, probably never seen 
before, will show themselves. 

Here we have taken two plants which, since 
the beginning, have been storing up traits; each 
working out its own destiny; each separated 
from the other, perhaps by a mountain range or 
a lake, and thus never before brought to a place 
where those heredities could combine; then in a 
single season, through combinations, we produce 
the seed for a new daisy reflecting every con- 
ceivable blend of those different heredities. 

When we plant this seed the following spring, 
\ve shall have pure orange daisies, pure white 
daisies, perhaps pink ones, yellow ones; daisies 
large and daisies small; daisies with big black 
centers, and daisies in which the centers are col- 
ored the same as the rays. 

We shall find some a deeper orange than the 
orange daisy because the balance which has de- 
termined the established shade of orange has 
been upset. 

We shall find purer whites than the white daisy 
ever knew as a result of the combination. 



THE CALIFORNIA POPPY 
TURNING WHITE 

A nearly white California poppy is 
sometimes found growing wild. After 
several years' selection these product 
pure white flowers from seed,, and by 
further selection will ff come true" from 
seed. 



DEVELOPING CHARACTERS 189 

We shall find daisies with rays whose color 
front and back is the same, and daisies with dif- 
ferent colors inside and out. 

We shall, in short, find all of the old inherit- 
ances of the flower and of the combinations of 
them all of the colors, shapes, sizes, forms, ele- 
ments of strength or weakness uncovered be- 
fore us. 

And between the white and the orange we 
have but to select the particular flower of our 
fancy. 

If the flower we select, perchance, showed 
some weakness, or if its tint were a little too light 
or too dark, or if for any other reason among 
this infinite color variation we did not find the 
exact result we sought, another season or still an- 
other would surely bring it forth ; for next year, 
instead of planting white and orange, we should 
plant a selection of our new daisies, and instead 
of getting a combination of two parentages, we 
should get a combination of combinations. 

Then, having secured the color called for in 
our original mental blue print, we might find 
structural improvements to make in the flower 
we might want to increase its height or to 
lengthen the daily period of its opening, or to 
rearrange its rays into a more chrysanthemum- 
like form, or to increase or decrease the size of 



190 LUTHER BURBANK 

its center or to accomplish any one of a num- 
ber of other ideals which we may have set up for 
our production. 

So on we go, season after season, always select- 
ing, obtaining one this year which bears seeds for 
next, with the bees and the winds anxious to 
carry on the work, if we are too lazy or do not 
have the time; narrowing our lines of heredity 
down and down until finally some day maybe 
fourteen months after the experiment began, or 
maybe fourteen years, we can say: "Here is a 
plant such as no man ever saw before here is 
the exact plant which we have planned." 

"But will the seed of this new daisy," some 
one asks, "produce more daisies of this same 
color?" 

Of all of the seeds of that daisy there might 
not be one which would reproduce the color which 
we have obtained. The seeds of that daisy sown 
together in a bed may be expected to show as 
great a variation as the seeds of the white and 
the orange exhibited when they were first planted 
after the bees and the winds had done their 
work. 

But there need be no discouragement. By di- 
viding the roots of many plants or raising them 
from slips or cuttings we can, in a single season, 
from a single plant, produce a great quantity of 



DEVELOPING CHARACTERS 191 

plants each similar to the original plant, be- 
cause each, in fact, is a part of the original 
plant. 

But by keeping our new pink daisies together 
year after year, in perhaps six years or ten or 
fourteen, pink being crossed with pink, and the 
equilibrium restored, we should find that we were 
getting seeds which would come true, or nearly 
true to type. 

We greatly disturb heredity to produce varia- 
tions; then we select the variation which pleases 
us and fix it by further selection and repetition. 

The architect can always build a second struc- 
ture better than the first, and the plant improver 
likewise finds in each experiment a multitude of 
new suggestions for the production of still other 
changes and improvements. 

In even the handful of daisy variations which 
can be reproduced here there are to be seen 
countless new tendencies, any one of which might 
lead to the perfection of a wholly different, if not 
a better flower. 

There are, of course, the variations in size 
and those with the long petals show that with 
encouragement the flower, simply by quantity 
production and continued selection, might pro- 
duce an offspring with blossoms much larger 
than those of either parent. 



"STAR" CHILEAN WILD 
FLOWER 

Three thousand six hundred varieties 
of wild flowers have been sent me by 
one collector in Chile, the major part 
of which are unnamed and unclassified. 
Here is one that shows interesting 
peculiarities of petal that give it dis- 
tinction anywhere. r Also it is beautiful, 
as a glance at the picture shows. 



DEVELOPING CHARACTERS 193 

Some may exhibit a tendency toward double- 
ness which gives rise to the thought that the 
new daisy, if desirable, might be made as double 
as our roses and carnations; in fact, this has al- 
ready been done. 

In other variation it might be noted that some 
are pink, yellow, or intermediate colors, while 
others may show deep red or purple streaks on 
the backs of their rays. From these it might 
reasonably be expected to produce a daisy hav- 
ing one color within and another color without. 

From the bed of seedlings with no two daisies 
exactly alike, there might be prepared a list of a 
thousand different tendencies, each susceptible 
of cultivation, each the possible starting point of 
some new r transformation. 

It is only when the life history of a plant, with 
all of its divergent tendencies, is uncovered in 
some such way as this, that the plant architect 
can see the full possibilities of further improve- 
ment. 

The daisy which we use especially for the pur- 
pose of illustrating this chapter may, or may not, 
be a desirable production it may or may not re- 
pay the thought and effort which it cost but it 
shows the simplest method which the plant archi- 
tect has within his reach a method which, ap- 
plied in the same way toward the accomplishment 

Vol. 1 Bur. Q 



194 LUTHER BURBANK 

of a more utilitarian purpose, has meant and will, 
more and more, continue to mean untold for- 
tunes of added wealth to the world. 

In order that the illustration may be com- 
plete, let us sketch some of the possibilities of 
employing this method. 

Let us begin with some garden vegetable 
which for centuries has been acquiring traits 
along the lines in which we have encouraged 
it working away, always, from the wild, 
and toward the accomplishment of our 
ideals. 

Let us say that we have been selecting it, un- 
consciously perhaps, for its tenderness, or sweet- 
ness, or early ripening, or productivity, or along 
any line which has made it more desirable or 
more marketable. 

Its evolution, then, has been simply a slow 
response to a new environment which for the 
first time in its history included man. 

Suppose, now, that we desire to work, in a 
single season or a dozen seasons, an improve- 
ment in this vegetable which will overshadow all 
of the improvement which countless generations 
of cultivation and unconscious selection have 
wrought. 

Our first step is to secure its wild counterpart 
inedible, maybe; sour, perhaps; tough, no 



DEVELOPING CHARACTERS 195 

doubt; wholly undesirable as compared with the 
plant which the seed bought at any grocery store 
will produce. 

Nevertheless, in the wild brother of our plant 
there is confined an infinity of old heredity just 
as an infinity of old heredity was confined 
in those two daisies; and the bees and the 
winds can bring forth variation between the 
tame and the wild just as striking and just 
as widely divergent as the variations in the 
daisies. 

Without doubt the first attempt to combine 
the heredities of tame and wild might produce no 
improvement only retrogression. But if we 
make numerous selections from a multitude of 
plants, we shall soon see before us evidences of 
all of the tendencies of the plant which, though 
perhaps not desirable, point the way to an end 
worthy of accomplishment. 

Then, instead of working with a single wild 
and a single cultivated plant, if we seek out a 
dozen wild plants or a hundred of them some 
plants from mountain environments and some 
from swamps, some from rich woodland soil, 
and some from the desert, we shall get a still bet- 
ter idea of the possibilities stored within the 
plant which need only combination and selec- 
tion to bring forth a perfected product. 



A BED OF CHINESE 
PINKS 

Here large numbers of the Chinese 
pinks have been allowed to run riot, 
that each plant might prove its capac- 
ities in competition with its fellows. 
Each day we go through such a bed, 
singling out and marking the half 
dozen or so plants that most fully meet 
approval. 



DEVELOPING CHARACTERS 197 

Or, suppose we have a tree which bears de- 
licious fruit in small quantities. 

Let us then find one with a tendency to over- 
produce, even though its fruit, in size, flavor, and 
appearance, be inferior. 

In some combination between the two, simply 
by following the leads which those combinations 
themselves will give, we shall in a few years, very 
likely, discover one variation which combines the 
productiveness of one strain of heredity with the 
deliciousness of another. 

Or, perhaps, we have a plant which bears us 
berries of wonderful flavor, but too small to be 
marketable. 

Let us find a plant with large, beautiful ber- 
ries, even though they be insipid, and see if, be- 
tween the two, by matching heredities, there is 
not to be found some new berry which is luscious, 
large, and beautiful. 

Or, supposing that in our own particular soil 
there are varieties we should like to grow which 
fail to prosper, while other less desirable varieties 
thrive. 

Our problem, then, is but the combination 
of heredities to bring the desirability of one 
with the hardiness of another into a single 
new plant which, as it were, we make to 
order. 



198 LUTHER BURBANK 

Or, if there is a variety which will not with- 
stand the rigor of our winters, perhaps it can be 
combined with a poorer variety which has been 
educated to them. 

Or, on the other hand, if there is a plant which 
withers in the heat of our summers, perhaps some 
combination can be effected with an already ex- 
isting brother or cousin, which, throughout the 
generations, has conquered the obstacle of heat. 

And so on throughout the whole world-wide 
range of environment. 

We shall find plants which have grown accus- 
tomed to the wet, and plants which are hardened 
to the dry; plante which thrive in heat and plants 
which thrive in cold ; plants which like sandy soil, 
and plants which can do well even in clay; plants 
which have become used to the glare of the sun, 
and those which live retiring lives in the deepest 
recesses of the shade; plants which bear flowers 
large and small, early and late, of short seasons 
and of long, fragrant and unscented, simple and 
complex. We shall find fruit flavors which are 
sour, sweet, acid, bitter; fruit skins which are 
smooth, fuzzy; fruits themselves that are large, 
small, even irregular, coarse, delicate; we shall 
find those which will stand shipment across a 
continent and those which spoil as soon as they 
are picked. 



DEVELOPING CHARACTERS 199 

We shall find a range of differences in wild 
plants, as great as the range of environments 
in which they have grown. 

And we shall find a range of differences in 
cultivated plants as great as the range of differ- 
ences in races and nations and individuals who 
have grown them. 

I saw an interesting illustration on the rela- 
tion between heredity and environment at the cir- 
cus one day. 

There, in a wire cage, was a tiny dog together 
with a lot of monkeys. 

While I was watching, a trainer appeared and 
snapped his whip. 

The monkeys quit their play with the dog, 
ran around in a circle, and climbed up the wire 
of the circular cage. 

The little dog followed them, but could not 
climb. He would start up and drop back, start 
up again and drop back again. 

Then he would look down at his feet, and if 
a dog ever showed surprise, that dog did. He 
seemed to be wondering why he could not climb 
as monkeys do. 

The environment was there, but the heredity 
was different. 

We see the same thing in plant life. The 
sweet peas with their tendrils and the nas- 



SAMPLE OF AN IMPROVED 
GLADIOLUS 

One of the thousands of variations 
my own work with the gladiolus has 
brought forth new colors and new 
combinations of color. The short stalk 
which makes staking unnecessary was 
developed on my grounds nearly forty 
years ago. The thick petals and last- 
ing qualities of the flower originated 
here. The double gladiolus and the 
gladiolus which blooms all around the 
stalk like a hyacinth, first appeared 
here. 



DEVELOPING CHARACTERS 201 

turtiums with their leaves can climb like the 
monkeys, while other plants can not be forced 
to climb because there is no climbing heredity 
within them. 

You may try to make corn climb a hop pole, 
or to make hops grow straight in the air without 
a pole or string. But in a lifetime you cannot 
succeed. 

It is heredity, heredity, heredity. Environ- 
ment, unless oft-repeated, only serves to bring* 
heredity out. 

The climbing monkeys and the disappointed 
dog show us an important truth in our work. 

If we want to take advantage of a climb- 
ing tendency in a plant let us by all means 
find a plant in whose heredity that climbing 
tendency is a part. Let us not try to teach 
monkeys to bark, or dogs to swing from th 
limbs of trees by their tails; let us not try 
to make corn climb the hop pole, or hops be- 
come shade trees. 

Maybe these things could be done. In fact, 
with unlimited time, there is no question that they 
could. But with plenty of plants about us with 
ready-made heredities of which we can avail our- 
selves in a single season, it would be folly to try 
to accomplish the same result in a harder way, 
well knowing that only the thousandth or mil- 



202 LUTHER BURBANK 

lionth generation ahead of us could see the re- 
sults of our work. 

In our search for heredities we shall find many 
plants which are scarcely worth working with 
[plants whose environments have not led into 
heredities which are desirable for our ends. 

But at the same time we shall find thousands 
of plants in the least expected places which, at 
first, seem impossible of use which with a little 
encouragement yield us rare heredities for our 
work. 

When the masons, carpenters, and decorators 
have finished the architect's house, and the keys 
are turned over to the new owner then, and 
from that moment, the structure begins to de- 
preciate until it crumbles in decay. The furni- 
ture movers dent the stair rails, the children 
scratch the doors, dust begins to darken and de- 
stroy the luster of polished surfaces; and the 
sun and night, and the frosts and the thaws, rain 
and the heat, slowly and irresistibly carry the 
structure on its downward grade. 

But when the architect of plants has com- 
bined old traits into the production of his ideal, 
he has fashioned something which, if his work is 
well done, the suns, and rains, and frosts, and 
winds will not depreciate; he has produced a liv- 
ing thing which, in spite of discouragements, and 



DEVELOPING CHARACTERS 203 

neglect, and abuse, will keep on, and on, and on 
improving as it goes. 

How few, indeed, are the materials which the 
architect of buildings has at his command when 
compared with the range of living traits which 
the architect of plants may call into play! 



Our search, then, is a search for 
stored-up heredities a search for; 
living traits. 



SHORT CUTS INTO THE CEN- 
TURIES TO COME 

BETTER PLANTS SECURED BY SELECTIVE 
EVOLUTION 

"\ Tf 7ITH the bees buzzing about in the 

\ \ thousands of blossoms on your experi- 
ment farm," said a visitor, "I should 
think that the plants would get all mixed up; I 
should think that the daisies would be crossed 
with carnations, and the carnations with balloon 
flowers, and the balloon flowers with poppies, 
and the poppies with cactus." 

If we were to watch a bee at work, we should 
quickly discover one reason why this does not 
happen one reason, at least, why cherries, 
prunes, roses, and geraniums have not long ago 
been reduced to a scrambled mess. 

Our observation of the bee would show that, in 
going from flower to flower, it goes usually to 
flowers of a kind. 

We should see that, if it starts in the morning 
with clover, it visits no other blossom during the 

205 



206 LUTHER BURBANK 

day but clover blossoms. Or if it begins on an 
orange tree, it passes the cherries, the peaches, 
the apples and anything else which may be in 
bloom, but will go miles to find orange trees; or 
if it starts on onions, then the geraniums and the 
carnations and the poppies have no attraction 
for it. 

Which, by the way, is the reason that the bees 
produce, for themselves and for us, clover honey, 
and orange honey, and onion honey, each with a 
distinct flavor of its own. 

But there are other reasons why the flowers do 
not get mixed up. 

One is that while some flowers advertise to 
the bees, others advertise only to the hum- 
ming birds and bees cannot get to the honey 
in the bird flowers and bee flowers do not in- 
terest the birds; some flowers open in the 
early morning, and some toward noon; some 
in the night; some bloom in April, and some 
in July. 

There are structural as well as other differ- 
,ences between the various families of plants 
which make cross-pollination impossible; and so 
on through a wide range of reasons why certain 
plants are not readily mated with others which 
will lead us, in a later chapter, into the interest- 
ing study of plant affinities. 



SELECTIVE EVOLUTION 207 

The bees help us to make new daisy colors be- 
cause, through heredity, the daisies of our first 
planting gave daisy nectar, though their colors 
were white and orange. And in a few cases 
which we might try, we could safely intrust the 
work of pollination to the bees, or birds, or other 
messengers with whom the plants have built up 
partnerships. 

But in the most important we should find that 
the pollination would have to be done only by 
hand. 

If, for example, we desired to effect a com- 
bination between two flowers, one of which 
blooms in the spring and the other in midsum- 
mer, the bees could be of no service. We should 
have to take the pollen of the early blooming 
flower and carefully save it until it could be ap- 
plied to the other. 

If we desired to effect a combination between 
a bird flower and a bee flower, even if in bloom 
at the same time, we should find it necessary to 
attend to the pollination ourselves. 

If we had it in mind to effect a cross between 
a particularly large, insipid plum and a small, 
highly flavored plum of another species, or if we 
desired to effect a cross between any two selected 
parents, we should find it necessary to do our own 
work of pollination. 



AT THE DOOR 

Even the flowers that grow beside 
my home are always undergoing obser- 
vation and being tested as to their 
capacity for further education. So pic- 
tures taken in different seasons do not 
have the same appearance. At the 
moment, this beautiful rose has the 
place of honor as the decoration selected 
for the porch. This rose is the Corona 
a primroselike seedling of Crimson 
Rambler. 



SELECTIVE EVOLUTION 209 

It would seem that much of the ingenuity 
evident in nature is directed toward a twofold 
end: 

First, toward producing an endless combina- 
tion of heredities in plants of the same kind 
which, to give them a name, we may call crosses. 

And second, to prevent the combination of 
things out of kind which, to distinguish them 
from crosses, we may call hybrids. 

The first aim insures infinite variation the 
mixing up of parallel strains of heredity in such 
a way that no two living things are exactly alike, 
and that, in each new balance of tendencies pro- 
duced, there is the possibility of an improvement. 

The second explains why, though all roses dif- 
fer from each other, yet all are roses why, 
though every living thing has its own individual- 
ity, its own personality, each bears the unmistak- 
able characteristics of its kind. 

"Here and there through nature, nevertheless, 
are hybrids. Are these accidents the result of 
some carelessness, some lapse?" 

Everything that is, is a definite part of the 
Scheme of Things. 

We see crossing between kinds and realize its 
tendency and purpose, and see its value in the 
Scheme, because it is going on about us always, 
everywhere because it is a quick-moving pro- 



210 LUTHER BURBANK 

cess which we can observe without doubt or 
difficulty. 

But when, on the other hand> we see the pro- 
visions in nature against crossing out of kind, 
those numberless ingenious devices designed to 
prevent the production of hybrids, we have no 
right to conclude that hybrids are not a part of 
the Scheme of Things. 

They are else there would be no hybrids. 

Crossing between plants of the same kind is a 
continuous active process necessary to the pro- 
duction of better and better individuals. 

Crossing out of kind, while more radical, is a 
process which has just as definite an end as cross- 
ing within kinds. 

Let us go back to our African daisies. 

If we read their history aright, there was, 
first, an orange flower which grew in the open 
veldt a flower which accommodated itself to the 
peculiarities of the soil and the air in which it 
grew, and to its plant, insect, and animal neigh- 
bors so that it became a thriving, successful 
race, each generation a little stronger each year 
seeing it increase in numbers and spread in ter- 
ritory. In its spread, we may well imagine that 
the winds, or the animals, carried its seed over 
otherwise impassable barriers just as human 
environment carries one son to New York to 



SELECTIVE EVOLUTION 211 

become a lawyer, another to Pittsburgh to be- 
come a steel maker, and another to the gold fields 
of Nevada. 

Thus reaching out, always into new environ- 
ments, some branch of this daisy family found 
itself in the midst of a clump of trees, trees 
which multiplied and grew till they obscured the 
sun and left the tiny plants in the obscurity of 
dense shade. 

As the trees grew (and just as slowly, quite 
likely), the daisies at their feet accommodated 
themselves to their new environment they 
adapted themselves to the shade and moisture 
they had less competition, perhaps, from other 
small plants and so became less sturdy they 
changed their color to the one best suited to at- 
tract available messengers of reproduction. 

At this point we interrupted the evolution of 
the African daisy by planting the white and 
the orange together and securing, in the 
pink one, an immediate blend of their divergent 
heredities. 

But it requires no stretch of the imagination to 
believe that, had we left them to their course, the 
same end would have been accomplished a cen- 
tury, or a thousand centuries, from now; that the 
same migratory tendency which took the white 
daisies into the woods would, in time, have 



212 LUTHER BURBANK 

brought them out of the woods and into the 
sunshine; or that the same tendency which got 
one division of the family into the woods 
would eventually have taken other divisions 
to the same woods; and that, sooner or later, 
there would have been white daisies growing 
alongside of orange daisies, so that, through 
the slow processes of nature, the same result 
which we produced by artificial means would 
have been achieved. 

And so, in all of our experiments with plants, 
we shall find that we are not working against 
evolution, but with it; that we are merely pro- 
viding it with short cuts into the centuries to 
come short cuts which do not change the final 
result, but only hasten its accomplishment. 

And who shall say that we, helping our plants 
to do in 1921 what without our help they might 
not be able to do before 3921 who shall say that 
we are not elements in evolution just as the 
bees, and the birds, and the butterflies, and 
the winds, and rains, and frosts who shall 
say that our influence, inestimably greater than 
any other influence in the life of a plant is 
not an integral part of progress in the Scheme 
of Things? 

In hastening evolution, we can, and do, play a 
more important part even than that of bringing 



SELECTIVE EVOLUTION 213 

about crosses, or hybrids, which the bees or the 
birds would never make. 

The greatest service which we render toward 
the advancement of plant life is that of selection, 
endless, skillful selection. 

The daisies were really, after all, the result, 
principally, of selection. The important thing 
was not to bring a mass of daisies together for the 
bees to work on; the important thing was to se- 
lect orange daisies, and white daisies, with the 
purpose of producing other colors. Then, with 
thousands of variations, we selected again this 
time for the colors we desired, and destroyed the 
rest. 

Afterward, with these new colors, we began a 
still further course of selection, selecting the 
largest, the hardiest, the tallest; and no matter 
how long we might continue to grow these 
daisies, we should keep on selecting, selecting, se- 
lecting each step in our selection, because it has 
the human mind behind it because it is actuated 
by purpose and desire each step in this selec- 
tion representing an advance, which, without 
our help, might take a hundred or a thousand 
years to bring about. 

So, in working out any ideal in plant improve- 
ment, the first factor and the last one is selection. 
Selection enters into the ideal itself, it enters 



THE NEW AMARYLLIS AND 
ITS PARENTS 

Having effected new combinations 
between species, in the amaryllis, a com- 
bination was made between genera. In 
this direct-color photograph print the 
improved amaryllis and its tiny parents 
are shown in exact proportion. The 
larger one is ten inches across. 



SELECTIVE EVOLUTION 215 

into every step of its accomplishment, and it 
enters into the production of every succeeding 
plant which represents that accomplishment. 

If you believe that nature makes no mistakes, 
and has no lapses, how can you account for the 
evident unfitness of so many individual plants 
to survive how can you account for the waste- 
fulness and extravagance which is apparent 
throughout all forms of plant life? 

Leaving nature out of it for the moment, let 
us look at the work which I have been doing here 
for fifty years. There has hardly been a time 
during this period when I have had less than 
twenty-five hundred experiments under way, and 
there have been seasons when from three to five 
thousand were in process. Estimating that on 
this three-acre home tract, considerably more 
than one hundred thousand definite, separate 
experiments in plant life have been conducted, 
in all. 

Some of the experiments which have taken the 
most time and cost the most money have pro- 
duced no apparent result; and some of the re- 
sults which seem most important have been 
achieved in the simplest way, with the least ex- 
penditure of effort. 

Out of the entire total of experiments tried, 
there have been not more than a few hundred 



216 LUTHER BURBANK 

which, so far, have resulted in a better fruit, or 
a better flower, or a more marketable nut, or a 
more useful plant that is enough better in all 
respects to warrant its introduction. 

On the other hand, I should feel repaid for all 
the work I have done if only a dozen of these 
experiments had turned out to be successes. It 
is in the very nature of experimentation we 
must try many things in order to accomplish a 
few. 

And this is just what is going on in nature alt 
the time excepting that where we might get 
one success out of forty failures, there might be 
but one out of a thousand or a million if the 
plants were left to work out their own improve- 
ment unaided. 

Then, after all, the unsuccessful experiments 
are failures only in a comparative sense. 

If you have ever watched the bridge builders 
constructing a concrete causeway, you must have 
seen the false construction which was necessary 
the stout wooden structure into which the 
plastic material was poured a costly structure 
in itself which was put up only to be torn down. 

We cannot call this wooden structure extrav- 
agance or waste, because it was a necessary step 
in the completion of the work. And so, while, 
in nature, we find many individuals which are 



SELECTIVE EVOLUTION 217 

weak many steps which look like backward 
steps instead of forward ones many apparent 
oversights, yet my own work has shown that this 
is true, that these are simply elements in a neces- 
sary scheme of false construction, without which 
the final object could not be achieved. 

The price of all progress is experiment, 
and successful experiment is brought about, 
always, at a terrific expense of individual 
failures. 

But who shall say that progress, any progress, 
is not worth all its costs? 

It is simply by eliminating steps and provid- 
ing short cuts, and bringing the human mind 
with its ideals, will, judgment, and persistence 
into the environment that we are able to produce 
new colors in a few months when, without our 
influence, nature might easily have taken till 
4020. 

The real work before us, then, is to study 
nature's processes to learn to read the history 
of plants, to uncover tendencies and understand 
their trends and then to provide short cuts so 
that the far distant improvement may be made 
a matter of months, instead of centuries. 

These short cuts and their application, from 
this point on, will be our principal study; per- 
haps a single illustration here, more comprehen- 



MORE THAN FIVE HUNDRED 
KINDS ON ONE TREE 

This direct-color photograph print 
shows one of my cherry trees which 
has produced as high as five hundred 
kinds of cherries at the same time this 
for the purpose of convenient compari- 
son and intelligent selection. 



SELECTIVE EVOLUTION 219 

sive than that of the daisy, will serve to give a 
clearer idea of their kind : 

Let us take, then, as a specimen, the methods 
employed in the production of a new cherry. 

First, as with the daisy, there must be an ideal 
some particular kind of cherry of which we 
have made a mental blue print. Let us say 
that our blue print calls for a large, sweet 
cherry, which will ripen early and bear long 
taking into account that appearance is a great 
factor. 

The first step would be to gather in our ele- 
ments; to pick out a large, beautiful cherry 
which, after the manner of many large, beauti- 
ful fruits, may be more or less insipid in 
taste; then to select another cherry, size and 
appearance inconsequential, which has the de- 
lightful flavor our plans and specifications 
call for. 

Let us take not one of each of these types, but 
a number of them, and then when they have 
bloomed, let us, by hand, cross them back and 
forth, making in all, we will say, five hundred 
crosses; each tied with a certain color of string 
for the purpose of later identification. 

The petals of the blossoms which we have 
crossed will fall away; long stems bearing green 
cherries will begin to take their place; and 



220 LUTHER BURBANK 

finally the twigs which we have marked with 
strings will reward us with their ripened fruit. 

There is an interesting legend of the French 
girls who used to take apple boughs in blossom 
and shake the pollen over the apple flowers of 
another tree, a legend of the wonderful variation 
in the apples which they secured. 

And here and there in our work we shall see 
a few exceptions to the general rule, which 
seem to prove that the French legend perhaps 
was founded on fact. 

These exceptions, which will form the basis of 
an interesting series of experiments for us later, 
need have no bearing on our present cherry 
work. 

For, as a matter of practical fact, we shall 
find no outward evidence of our work. The 
meat of the five hundred cherries w r hich we have 
crossed, we can safely assume, will taste the 
same, and be the same, as though we had let the 
bees attend to pollination; the cherries that re- 
sult will not be different in flavor or appearance 
from the other cherries on the tree. 

But inside the stony seed of each of those 
cherries we shall find an indelible living record 
of what has been done. 

So, disregarding the fruit, we save our five 
hundred cherry seeds and plant them in a shal- 



SELECTIVE EVOLUTION 221 

low box until they have sprouted and then trans- 
plant they till they attain a six or eight inch 
growth. 

So far, let us see how we have shortened 
nature's processes. 

In the first place, we. have brought together a 
large, insipid cherry and a homely, small, sweet 
one, brought them from points, perhaps, two 
thousand miles apart. 

In the natural course, those two cherries would 
have spread; they would, eventually, have come 
together, possibly; but we have brought them 
together without delay. Perhaps, in this, we 
have saved a thousand years. 

In bringing our two kinds of cherries to- 
gether we have brought not only one of each 
type, but dozens, or hundreds, each selected for 
its size, OB appearance, or some probable quality 
which it contains within. In this simple selec- 
tion of individuals we may have saved other 
thousands of years. 

With unerring accuracy we have seen that the 
pollen of the two kinds has been interchanged, 
so that the five hundred or so resulting seeds will 
represent the two heredities we wish to combine 
and only these. 

Who can estimate how long it might have 
taken the bees and the winds, working even in 



TWO SEEDLING TYPES 
OF CHERRIES 

They are shown here together* so 
that their similarities and differences 
may be seen at a glance. Yellow, pink, 
red, or purple cherries often come from 
the seeds of black ones, and these and 
other colors may come from seeds of 
any cultivated variety. 



SELECTIVE EVOLUTION 223 

neighboring trees, to effect specific crosses with 
the certainty which we have assured? 

Now, with new heredities bundled up in our 
five hundred cherry stones, we plant them under 
every favoring condition in our shallow box, and 
unless mishap or accident intervenes, we get new 
cherry trees from all, or, at worst, lose but a 
few. 

And now, wdth our sprouted cherry seedlings 
six inches or eight in height, with no man knows 
how many thousand years of nature's processes 
cut out, we come to one of the most important 
short cuts of all quick fruiting, so that there 
may be quick selection. 

Grafting is no new practice. 

Virgil wrote verses about it: 

But thou shalt lend 

Grafts of rude arbute unto the walnut tree, 
Shalt bid the unfruitful plane sound apples bear, 
Chestnuts the beech, the ash blow white with the pear, 
And, under the elm, the sow on acorns fare. 

Pliny, evidently a much more practical man, 
within the same century, describes a cleft graft 
and bespeaks the following precautions : that the 
/stock must be that of a tree suitable for the pur- 
pose ; that the cleft must be taken from one that 
is proper for grafting; that the incision must not 



224 LUTHER BURBANK 

be made in a knot ; that the graft must be f rom- 
a tree which is a good bearer, and from a young 
shoot; that the graft must not be sharpened or 
pointed while the wind is blowing ; that the graft 
should be inserted during the moon's increase; 
with the final warning, "A graft should not be 
used that is too full of sap, no, by Hercules! no 
more than one that is dry and parched." 

"Graft close down to the trunk," the later 
theory of grafting has been, "there the sap pres- 
sure is highest and the grafted cion has the best 
opportunity to live. 

"Graft away out at the tip ends of the tree 
and yon will save from two to seven years of 
time. 

"Grafting close to the trunk gives the cion a 
better opportunity." 

Give anything a good opportunity and it takes 
its own time to mature. 

Take away that opportunity, and responding 
to the inborn tendency of every living things to 
reproduce itself, it will hasten the process with- 
out waiting to accumulate strength. Therefore, 
if we graft away out at the tip ends of the tree, 
while we make it harder for the cions to exist, 
yet, in consequence, they will bear much sooner. 

Furthermore, if we graft close to the trunk, 
we can, at best, attach but a few cions. 



SELECTIVE EVOLUTION 22,3 

But if we graft out at the tip ends, we can put 
five hundred or more cions on a single tree. 

By grafting the smaller branches, fruit pro- 
duction is greatly hastened, cutting from two to 
seven years out of the long wait for the fruit 
which is to tell the story of the heredities which 
are confined within the seed. 

It is possible, at this point, to give but the 
barest glimpse of the results which this mode 
of grafting made possible. Under the proper 
heading, the details will be fully explained, to- 
gether with a summary of the results of hun- 
dreds of thousands of grafts, showing that, while 
the average time of fruiting has been brought 
down to less than two seasons, in some excep- 
tional cases fruit has been secured for testing 
the same season that the graft was made. 

Here, too, it is not possible to convey more 
than a general idea of the plans which, in every 
operation, are aimed toward the end of produc- 
ing the quickest possible test. Whether it be the 
quince seedlings bearing fruit the first year or 
yearling chestnut trees loaded down with nuts; 
or ten year old walnut trees, the size of their 
century old cousins all through this work 
the plan and the method is to save time for the 
individual plant as well as to provide short cuts 
for the process of evolution, 

Vol. 1 Bur. H 



SOME OF THE 400 COME 
TO JUDGMENT 

This picture (reduced about one- 
half) shows ten of the hundred or more 
varieties of cherries picked on the same 
day from the same tree, and laid out 
for examination and selection. As new 
combinations are effected each season 
through cross-pollinization, there are 
always unique varieties to be found on 
the tree each June time. New varieties, 
may, of course, be perpetuated by 
grafting. 



SELECTIVE EVOLUTION 227 

To go back to our cherry seedling, now six 
inches above the ground, if we were to depend 
on nature's processes, by careful planting and 
cultivation we might, with care, produce cher- 
ries in seven years, but, by the above method, we 
shall have our cherry crosses in 1920 instead of 
in 1927 five hundred of them all on a single 
tree, so that they can be plucked and laid out, 
first, for a visual selection, to select the ones 
which conform to our ideas of color, size, and 
beauty; and, second, for selection through taste 
to find the one, or the two, or the dozen among 
them which come the nearest the ideal of oui 
original mental blue print. 

Perhaps of five hundred cherries spread be- 
fore us none may fit the blue print; or perhaps 
one or two approximating it may show signs 
of further improvements which ought to be 
made. 

Eliminate the rest, and start afresh with these 
two begin at the very beginning with them 
again grow more seedlings, produce quick fruit 
through grafting, and select again. 

Every little while I have, as the neighbors 
choose to call it, a $10,000 bonfire. 

In such a bonfire there might be 499 cherry 
plants out of the five hundred which we have 
just matie; there would be 19,999 rose bushes 



228 LUTHER BURBANK 

which had been brought to blooming in order to 
find the twenty thousandth which was not burned 
or perhaps twenty thousand rose bushes, the 
one sought for not having been worth the saving; 
there would be 1,500 gladiolus bulbs with market 
value of half a dollar apiece, put in the fire after 
the one, or the two, or the dozen best among 
them had been selected; there would be twenty 
thousand cactus seedlings, representing three to 
five years of care and watchfulness, but useless 1 
now, their duty done. A ten thousand dollar 
bonfire, indeed, without exaggeration. 

The builder of bridges can sell the lumber used 
in his false construction for seconds; and so I 
could profitably dispose of the elements of false 
construction in my work those millions of seeds 
and bulbs and cuttings which represent second 
bests or poorer; but every step in the process ex- 
cepting those concerning the final result is ob- 
literated with a ruthless hand. 

^t is better to run the risk of losing a perfected 
product, through the destruction of the elements 
which went into it, than to issue forth to the 
world a lot of second bests which have within 
them the power of self-perpetuation and multi- 
plication, and which, if we do not destroy them 
now, will clutter the earth with inferiority or 
mediocrity. 



SELECTIVE EVOLUTION 229 

So we see that, while nature might eventually 
produce the things which we hasten her to pro- 
duce, yet the improvements would find them- 
selves in competition with the failures which 
they cost, the failures outnumbering the improve- 
ments, perhaps, a million to one. We see that 
we not only shorten the process, not only achieve 
a result out of every thousand failures instead of 
every ten million, but we give our product the 
advantage of a better chance to live we remove 
from it the necessity of fighting its inferiors 
for the food, and air, and sunlight which give 
it life. 

This, then, is the story of the making of a new 
cherry to fit an ideal: 

First, selection of the elements; second, com- 
bining these elements; third, bringing these com- 
binations to quick bearing; fourth, selecting one 
out of the five hundred; and then, selection, on 
and on. 

These, after all, are but details in the process 
minor details, in fact. 

The big element, overtowering them in im- 
portance, is selection. 

First, the selection of an ideal, then the selec- 
tion of the elements which are to be blended to 
achieve it, then the selection of the resultant 
plant, end after that the selection of better and 



230 LUTHER BURBANK 

better individual plants to bear the fruit which 
reproduces the original selected ideal. 

Everything we do, then, is simply done to 
facilitate selection. 

We produce new plants in enormous quanti- 
ties, in order that there may be many from which 
to select; and having selected, we destroy nine 
hundred and ninety-nine one thousandths of our 
work. 

We strive all the while to produce quick re- 
sults to eliminate the long waits and to shorten 
those that we cannot wholly eliminate simply 
so that our selection may be truly comparative 
as that of five hundred fruits tasted in a single 
afternoon, and so that lingering expectancy may 
not prejudice our judgment, or the result. 

It took two thousand years or more to bring 
about the juicy American pear by unconscious 
selection and two thousand years for the Ori- 
entals to produce the pear they liked. 

Yet, as plant improvement goes, the pear was 
quick to respond to its environment; other fruit 
improvements wrought through unconscious se- 
lection have taken ten times as long. 

On the other hand we see the cherry tree, bear- 
ing more than five hundred different kinds of 
cherries at the same time, cherries produced to 
compare with a mental blue print less than three 



SELECTIVE EVOLUTIOX 231 

years old among which one, at least, will be 
found, which will lead to achievement of the 
ideal. 

And, similarly, in every department of plant 
life, whether it be in farm plants, garden plants, 
forest plants, lawn plants, or orchard plants, or 
whether it be in plants which we grow for their 
chemical content, or for their fibers, or what 
we shall find that it is possible to devise short 
cuts into the centuries to come, and through com- 
bining stored-up heredity with new environment, 
to hasten evolution to produce for us entirely 
new plants to meet our own specific desires. 



Who shall say that progress is not 
worth all its costs? 



HOW FAR CAN PLANT 
IMPROVEMENT GO? 

THE CROSSROADS WHERE FACT AND THEORY 
SEEM TO PART 

WHEN I first began this work I was 
taught that a combination between two 
varieties of the same species was possible 
that I might cross one plum with another 
plum, for example, to get a new variety but 
that the species marked the definite boundary 
within which I must work. The science of that 
day was firm in its belief that a seed-bearing, 
fixed, self -reproductive cross between plants of 
different species was beyond the pale of possi- 
bility. 

A little later on, when I succeeded in com- 
bining the plum with the apricot, and produced, 
thereby, a new fruit whose parents were of 
undeniably different species, the law. or rule, was 
moved up a peg; and I was told that while it 
might be possible to effect combinations between 
different species, yet that must be the limit of 

233 



234 LUTHER BURBANK 

accomplishment; that combinations between the 
next higher divisions, genera, were beyond the 
power of man to effect. 

Then when I was able, after a time, to take 
parents of two different genera, like the crinum 
and the amaryllis, and a score of others 
which might be mentioned, and to effect suc- 
cessful seed-producing combinations between 
them, I began to hear less and less about laws 
and rules. 

The fact is that the laws and the rules are too 
often man-made. 

Nature, herself, has no hard and fast mode of 
procedure. She limits herself to no grooves. She 
travels to no set schedule. 

She proceeds an inch at a time or a league 
moving always, but apparently into an un- 
mapped, uncharted, trackless future. 

I like to think of nature's processes as end- 
lessly flowing streams in which varied strains of 
heredity are ever pouring down through river 
beds of environment; streams which, for ages, 
may keep to their channels, but each of which 
is apt, at any time, to jump its banks and find a 
different outlet. 

Just about the time we decide that one of 
these streams is fixed and permanent, there is 
likely to come along a freshet of old heredity, or 



FACT AXD THEORY 235 

a shift in new environment ; after which we must 
rebuild our bridges and revise all our maps. 

Since the subject of classification is an impor- 
tant one; and since I have at times upset some 
man-made laws or theories it may be well, at this 
point, to take a bird's-eye glimpse over the maps 
and charts which have been worked out. 

With a subject in which the bulk of truth is 
masked in the obscurity of past ages, and with 
many men of many minds attacking it from 
many viewpoints, it is only to be expected that 
there should be differences of opinion. 

But, for the sake of making the explanation 
clear, we may for the moment overlook minor 
divergences and view only the main backbone 
plan which meets with the broadest acceptance. 
To begin at the beginning, we see first, spread 
before us, three kingdoms whose boundary lines 
are well surveyed and whose extent is all-inclu- 
sive. These are the mineral, the vegetable, and 
the animal kingdoms. 

Our interest lies now in the vegetable king- 
dom, which bridges the space between the other 
two. This kingdom first divides itself into six 
(perhaps seven) branches, or subkingdoms, 
called phyla. 

The lowest of these subkingdoms includes only 
those vegetables of the simplest type which re- 



236 LUTHER BURBANK 

produce by splitting themselves into two or more 
individuals. In this subkingdom live the death- 
dealing bacteria, which bring about such human 
diseases as tuberculosis and malaria, or such 
plant diseases as black rot; and our helpful bac- 
teria, too, which are everywhere helping us to 
digest our food, and without whose help the 
higher subkingdoms of plant life could not exist ; 
and other plants of the same grade. 

The next subkingdom, higher by a step, in- 
cludes the yeast which we use to raise our bread, 
or those, microscopic vegetables which turn hop 
juice into beer, apple juice into cider; and others. 
Those who prefer to chart seven subkingdoms 
instead of six, divide this branch into two, making 
the slime molds a separate phylum. 

The next subkingdom, ascending the scale, in- 
cludes, among others, the mosses and liverworts. 

From these it is but a step to the next sub- 
kingdom, which includes the ferns the highest 
type of flowerless plants, and the first, in the 
ascending scale, to exhibit a complete develop- 
ment of root, stem, and leaf. 

The final subkingdom, and the one into which 
our work principally takes us, embraces those 
plants which produce seeds. 

Taking, then, this latter, the highest sub- 
kingdom, we find that it separates into two broad 



FACT AND THEORY 237 

divisions, called classes, one of which is distin- 
guished by bearing its seeds in inclosed packages 
called ovaries ; the other bearing seeds which are 
exposed or naked. The first of these classes 
includes the vast majority of seed-bearing 
plants; the other including principally those 
trees, like the pine and the cypress, which bear 
their seeds in open cones. 

Next on our chart we shall find that the class 
is subdivided into orders. The order represents- 
a collection of related families. As an example, 
the order Eosales is made up of the rose family, 
the bean family, the cassia family, the mimosa 
family, and twelve other families closely allied. 

Below the order comes the family a division 
which is still broadly inclusive; the rose family 
for example taking in not only the rose itself, 
but the apple, the blackberry, and sixty-two 
other plants whose close relationship might not 
at first be evident. 

From the family we next narrow down to the 
genus which separates the rose from the apple 
and the blackberry and gives each its own classi- 
fication. 

Beneath the genus comes the species. 

And beneath the species the variety. 

We may take it as a safe observation that 
the simpler the form of life, the less the 



SOME HYBRID BLACK- 
BERRY CANES 

It is quite possible, from the appear- 
ance of the cane of the blackberry at 
certain stages, to predict the color of 
the fruit which is later to be borne. 
The application of this short cut is 
fully explained under a later heading. 
The picture opposite shows a range of 
variation produced by crossing. 



FACT AND THEORY 239 

tendency toward variation; the more complex, 
the greater the opportunity for individual 
differences. 

So, in the simpler subkingdoms, and in the 
more general divisions down to and includ- 
ing the order, the lines of division are more 
readily differentiated, and the work of classi- 
fication has been fairly free from differences of 
opinion. 

But as the order breaks up into families, and 
the family breaks up into genera, and the genus 
breaks up into species, and the species breaks up 
into varieties, and variations tend more and more 
to carry the individual away from its kind, there 
are to be found dissensions and differences of 
opinion which could hardly be chronicled in 
eight full volumes of this size. 

Nor is the divergent opinion surprising. 

It is said that, of an iceberg floating in the sea, 
but one-eighth is visible to the surface observer, 
while seven-eighths of the mass is submerged 
beneath the water line. 

Who, from looking at the one-eighth in view, 
could be expected to draw an accurate detail 
picture of the iceberg as a whole? 

The vegetable kingdom which presents itself 
to our vision to-day has been under close scientific 
observation, at most, but a few hundred years. 



240 LUTHER BURBANK 

It has behind it, who shall say, how many tens 
of thousands of generations of ancestry which, 
coming before man, went by unobserved yet 
which, under new environment, are continually 
bursting forth to confuse us. 

How can man, with only one ten-thousandth 
of his subject revealed to him, be expected to 
make charts or maps which shall withstand on- 
slaught, or be superior to criticism? 

For the sake of ready understanding we may, 
however, summarize plant life into the broad 
classifications outlined above. 

First, the vegetable kingdom, which includes 
all plants. 

Second, the subkingdom or phyla, six or seven 
in number. 

Third, the class, which ranks above an order 
and below a phylum. 

Fourth, the order, which ranks between the 
class and the family. 

Fifth, the family, which ranks below an order 
but above the genus. 

Sixth, the genus, which ranks below a family 
but above the species. 

Seventh, the species, which ranks below a 
genus and above the variety. 

Eighth, the variety, which ranks below a 
species and above the individual. 



FACT AND THEORY 241 

Yet with but one certainty in the entire scheme 
of classification that certainty being the indi- 
vidual itself. 

Men may tell us that a plant belongs to one 
genus or to another, that it is of this species, or 
of that or that it is even of a different family 
than at first we thought but these, after all, are 
but theories, built up about the plant by man 
theories which serve merely as guideposts in our 
work. 

The plant itself, the individual plant, if we but 
watch it and give it an opportunity, will tell 
us for itself, beyond dispute or denial, just what 
manner of plant it is just what we inay hope 
for it to do. 

Next in importance to classifying plants, from 
a superficial standpoint, is a method of naming 
them. 

When we go to the florist's we ask for roses, 
or marigolds; when we go to the fruiterer's we 
talk to him of oranges, and plums, and cherries; 
when we go to the green grocer we ask for let- 
tuce, or cabbage, or peas; when we select furni- 
ture we talk of it as being made of mahogany, 
or oak, or walnut. 

Thus, commonly, we call all forms of plant 
life by their nicknames and by their nicknames 
only do most of us know them. 



242 LUTHER BURBANK 

One reason, likely enough, is that the scientific 
names of plants are in Latin for the good 
reason that the Russian, or Swedish, or Spanish, 
or American scientist is able to describe his 
work, thus, in a common language. 

In giving a plant its Latin name, no attention 
is paid to its class, order, or family. 

The name of the genus becomes its first name. 

The name of the species follows. 

And the name of the variety, when given, 
comes last. 

Thus, in writing the scientific name for an 
apricot, or a plum, or a cherry, we should give 
first the name of the genus, which, for all of 
these, is Prunus. 

If we are to describe, for instance, a cherry of 
the species Avium, we should write, following 
the name of the genus, the name of the species, 
as Prunus Avium. 

And then, if we were to write the name of 
some particular improvement in that species of 
cherry, we should follow the names of the genus 
and species with the name of that variety, as 
Prunus Avium May duke. 

Or, if we were to prepare a technical article 
about this species, we should write Prunus 
Avium at the first mention of it, and contract 
it to P. Avium when mentioning it thereafter. 



FACT AND THEORY 243 

In this work, in order to gain clearness with 
the least effort, and to avoid confusion through 
the use of disputed terms, it has been decided, so 
far as possible, to call plants by their commonest 
names; going, wherever necessary, into a brief 
explanation in order to identify the plant clearly 
in the mind of the reader. 

Our work is to be a practical work, and the 
effort which it would cost to master thousands 
of Latin names might, it is believed, be better 
expended in a study of the principles and the 
practice. 

There arises, unfortunately, a confusion 
through use of common names. The California 
poppy, for example, is not a poppy at all; but 
for the purposes of this work it has been deemed 
best to call it the California poppy, by which 
name it is generally known, rather than to refer 
to it as Eschscholtzia; and so on throughout the 
list of other plants. 

No common name is used, however, which is 
not to be found in the dictionary; so that those 
whose scientific interest is uppermost have but 
to refer to their Webster, which gives a greater 
wealth of detail than could be hoped for in a 
glossary or an appendix to these volumes. 

A few years after I came to Santa Rosa, I 
was invited to hear a new minister preach on a 



244 LUTHER BURBANK 

subject which, I was assured, would be of inter- 
est to me. 

I was not in the habit of attending that church, 
so I tried to find my way to an unobtrusive seat 
in the rear, where I could disturb no one. But, 
as if by prearrangement, the usher would not 
have it that way I was led to the front center, 
where I was given a pew to myself. 

As soon as the sermon began, I saw the reason 
for it all. That preacher, with a zeal in his heart 
or perhaps better in his head worthy of a 
better cause, had evidently planned a sermon for 
my own particular benefit. He was determined 
to show me the error of my ways. 

He began by describing "God's complete ar- 
rangements," as evidenced in the plants about 
us, and rebuked me openly for trying to improve 
on the creations of Omnipotence. He held me 
to ridicule as one who believed he could improve 
perfection; he predicted dire punishment for 
attempting to thwart nature and tried to per- 
suade me, before that audience, to leave God's 
plants alone. 

Poor man ! Whatever may have been thought 

of his good taste, or his tact, or his judgment, 

I could hardly take offense at his sentiments 

for they really reflected the thought of that 

day. 



FACT AND THEORY 245 

He could not see that our plants are what they 
are because they have grown up with the birds, 
and the bees, and the winds to help them; and 
that now, after all these centuries of uphill 
struggle, man has been given to them as a part- 
ner to free them from weakness and open new 
doors of opportunity. 

He could not see that all of us, the birds, and 
the bees, and the flowers, and we. ourselves, are 
a part of the same onward-moving procession, 
each helping the other to better things; nor 
could many others of his time see it. 

And the botanists of that day, less than four 
short decades ago, found their chief work in the 
study and classification of dried and shriveled 
plant mummies, whose souls had fled rather 
than in the living, breathing forms, revealing 
their life histories. 

They counted the stamens of a dried flower 
without looking for the causes for those stamens ; 
they measured and surveyed the length and 
breadth of truth with never a thought of its 
depth they charted its surface, as if never 
realizing that it w T as a thing of three dimensions. 

And that is why those who had devoted their 
lifetimes to counting stamens and classifying 
shapes told me, through their writings, that a 
cross might be made within species, but never 



246 LUTHER BURBANK 

between species; that is why when I did make a 
cross between species they looked no further into 
the truth, but simply moved up a notch, and said, 
"Very well, but you cannot make a cross between 
genera"; that is why, when I did that very thing, 
not once, but several times, that type of scientist 
lost interest in rule making and went back to 
stamen counting. 

To realize the point more clearly, let us ob- 
serve for a moment the common tomato which 
belongs to that large division of plants, the 
Solanum family. 

Just as the rose family includes not only the 
rose, but the apple and the blackberry and hun- 
dreds of other plants, so the Solanum family 
includes seventy-five genera and more than 
eighteen hundred species. 

The classification is built around structural 
facts, such as that plants of this family originally 
had alternate leaves with five stamens and a two- 
celled ovary, or egg chamber, each cell contain- 
ing many eggs. 

These structural similarities in the plants of 
this family trace back to a common parentage 
and fully justify the classification of these 
seventy-five genera in a single family. 

If we were to look not at the structure, how- 
ever, but at the seventy-five genera themselves 



FACT AND THEORY 247 

then, and only then, could we fully realize 
the wonders which environment, blending with 
that common heredity within the plant, has 
wrought. 

We should see, among the seventy-five 
brothers and sisters of that family, if they were 
spread before us, the poisonous bittersweet, and 
the humble but indispensable potato; the egg 
plant and the Jerusalem cherry; the horse 
nettle and the jimson weed; the tobacco plant 
and the beautiful petunia; and the tomato 
itself. 

We should see seventy-five plants with orig- 
inal structural similarities, yet differing, in every 
other way, as night differs from day; and we 
should be able to trace, if we observed closely 
enough, the points at which, in the history of this 
family, new environment, oft repeated, has 
hardened into heredity, subject to the call of 
still new environment, which has not been lack- 
ing to bring it out ; we should be able to trace, by 
easy stages, why one branch ran to the poisonous 
bittersweet, another to the potato with its food 
product below the ground, another to the tomato 
with its tempting fruit displayed on the vines 
above; another to tobacco, valued for its chemi- 
cal content and so on throughout all of the 
variations. 



VARIATIONS IN WALNUTS 

The variations here shown were se- 
cured by crossing. In this walnut work 
nuts are grown by the wagonload for 
the purpose of finding one or two vari- 
eties which may approach the ideal 
desired. 















X00&2* 




mi 



FACT AND THEORY 249 

The tomato, we should see, was the last of the 
family to fall into a violent change of environ- 
ment. 

A tropical plant, bearing fruits about the size 
of a hickory nut and not believed to be edible, 
the tomato found its way into the United States 
within the past century. 

At first, the tomato plant was prized merely 
as an ornament; it was grown as we now grow 
rose bushes, and the fruit was looked upon as 
a mantel decoration until, by accident, it was 
discovered to be edible. There are, in fact, many 
such ornamentals to-day which might bear us 
edible fruit. One in particular, the passion 
flower, will form the subject of an interesting 
description later on. 

Following the discovery that the tomato was 
edible came the same course of unconscious selec- 
tion that falls to the lot of every useful plant. 
The finest tomatoes were saved and cultivated. 

In the environment of the tropics, the tomato 
fruit of hickory nut size was ideal; it cost less 
effort to produce than a larger tomato; it con- 
tained sufficient seeds to insure reproduction. 

But with the advent of man into its environ- 
ment, its seed chambers increased in number, the 
meat surrounding the seeds increased greatly in 
quantity and improved in quality; so that in 



250 LUTHER BURBANK 

virtually half a century the large, luscious, juicy 
tomato we now know is universally to be found 
in our markets, in season and out. 

No man can say how many thousands or tens 
of thousands of years it took wild environment to 
separate the tomato from the seventy- four others 
of its family. Yet, in less than half a century, 
see what changes man, as an element of environ- 
ment, has worked! 

We take the seeds of our Ponderosa tomatoes, 
and midsummer brings us new Ponderosas so 
well have we succeeded in fixing the traits we 
desire. 

But were we to take those same seeds to the 
tropics and plant them under the conditions of 
only fifty years ago an entirely different thing 
would happen. 

The first generation would be Ponderosas, 
more or less like those we grow here. 

But in the second generation, or, at latest, the 
third, the seeds of those very Ponderosas, when 
planted, would grow into vines which bear the 
old type of tomato the size of a hickory nut 
an immediate response, almost, to the wild 
tropical environment which prevailed before man 
began its culture. 

From the botanists of only a century ago, 
examining only dead tomato blossoms from the 



FACT AND THEORY 251 

tropics, and dried tomato fruits the size of 
hickory nuts how could we expect an inkling, 
even, of what the tomato with less than half a 
century of cultivation could become? 

How short, indeed, the time which environ- 
ment requires to transform a plant beyond 
recognition especially when man, either con- 
sciously or unconsciously, becomes a part of that 
environment ! 

And, knowing what the Orientals did to the 
pear, what the American Indian did to corn, 
what we have done to the tomato, can we not see 
that while stamen counting has its place, yet, 
for real achievement in plant improvement, we 
must look for help not so much to the stamen 
counters as to the plants themselves as new en- 
vironment brings their old heredities into view. 

How far, then, can plant combination be 
carried? Is it possible to go above the genus 
and make combinations between families? Or to 
go above the family and make combinations be- 
tween the orders ? Or to go above the orders and 
make combinations between the classes? Or to 
go above the classes and make combinations be- 
tween the kingdoms? 

The limitations of our work are not generally 
limitations imposed by nature; they are limita- 
tions imposed by the clock and the calendar. 



252 LUTHER BUKBANK 

Here we are, pitting ten thousand years of 
hardened heredity against five or ten years of 
new environment; sometimes we succeed. Is it 
any wonder that more often we fail? In five 
years, however, we can often work a practical 
transformation. 

Every season we are working changes which 
nature would take ages to work; but from a 
practical standpoint we must seek always to take 
advantage of the old heredities which nature has 
stored up to make them serve our ends, be- 
cause this can be done quickly; rather than to 
create and fix new heredities which might take 
so long as to rob our work of its usefulness. 

Before us is a world of living, onward march- 
ing plants which have made, are making, and will 
continue to make their own rules as they go 
along. Here before us, too, is the propaganda of 
our subject with its maps, plans, charts, rules, 
laws, theories, beliefs, built up all too fixedly, too 
arbitrarily, too superficially, perhaps, but very 
completely, nevertheless, around this onward- 
marching mass. 

Let us use to the utmost all the help that sci- 
ence can give ; to save time, let us accept the laws 
and the rules, let us have confidence in the maps 
and the charts, until the plants themselves show 
our error. 



FACT AND THEORY 253 

Let us search always, at least for present prac- 
tical use, for stored-up heredities; just as we 
would seek stored-up diamonds, or gold, or coal, 
instead of trying, by chemistry, to produce them. 

Great results are possible with time, but let us 
seek all the short cuts we can. 

For, after all, we have so little of time ! 

With time as our limiting factor, then, we 
shall find in plant work many things which we 
cannot hope to accomplish. 

We shall find plants, of course, of different 
species, and different genera as now classified 
a surprising number, in spite of the old belief, 
which will combine readily to produce fertile off- 
spring constituting a new species or a new genus. 

We shall find plants of different species or 
genera which combine to make a sterile offspring 
a mule among plants. 

And we shall find plants which can hardly be 
combined at all plants in which the pollen of 
one seems to act as a definite poison on the other 
and plants which, through long fixed heredity, 
seem as averse to combination as oil seems averse 
to combining with water. 

But no man can tell until he has tried tried 
not once, but a few thousand times perhaps. 

"What is that?" asked a seedsman who was 
visiting Santa Rosa. 



A HEAVY-BEARING 
SEEDLING 

This complex hybrid bears large 
bunches of grapes of uniform size and 
in enormous profusion. It has all the 
qualities of an ideal grape, for the 
fruit also is supremely delicious. 



FACT AND THEORY 255 

"That is a Nicotunia, and you are the first man 
in the world who has ever seen one. It is the 
name which I have given to a new race of plants 
produced by crossing the large flowering Nico- 
tiana, or tobacco plants, with petunias. It is, as 
you can see, a cross between two genera of the 
nightshade family." 

"H'm!" said the seedsman. 

You know the secret now, but if you think 
that you can produce these Nicotunia as you 
would hybrid petunias, or crossbred primroses, 
go ahead and try; there is no patent on their 
manufacture ; but if the five hundredth cross suc- 
ceeds, under the best conditions obtainable, you 
will surely be very successful. I do not fear any 
immediate competition. 

Perhaps those who have said that species could 
not be combined with species, or genus with 
genus, have tried only once or twice or a dozen 
times. Perhaps patience and persistence as well 
as a wider knowledge account for some of the 
upset laws. 

"Why not content ourselves to work within 
varieties as the bees work?" asks some one. 

Because by going out of the varieties and com- 
bining, we multiply almost infinitely the com- 
binations of old heredities which we may bring 
into play we lessen the work which we have to 



256 LUTHER BURBANK 

make environment do by spreading before us 
more combinations of heredity we accomplish 
in two years what otherwise might take two life- 
times. 

We see that the science of plant life is not yet 
an exact science, like mathematics, in which two 
and two always equals four. It is not a science 
in which the definite answers to specific problems 
can be found in any book. 

It is a science which involves endless experi- 
menting endless seeking after better and better 
results. 

Theories are good, because if we do not per- 
mit them to mislead us, they may save us time; 
laws, and maps, and charts, and diagrams sys- 
tems of classification and of nomenclature all 
these are good, because, if they are faulty, they 
still reveal to us the viewpoint of some one who, 
with diligence, has devoted himself to a single 
phase, at least, of a complex subject. 

But we must remember that the theories, most 
of them, are built around dead plants. 

While the facts we are to use are to be gath- 
ered from living ones. 

So, every once in a while, when we come to a 
crossroads where that kind of theory and this 
kind of fact seem to part, let us stick to the thing 
which the living plant tells us, and assume that 



FACT AND THEORY 25? 

evolution, or improvement, or progress, or what- 
ever we choose to call it, has stolen another lap 
on the plant historians. 

And let us remember that the fact that ours is 
not an exact science, with fixed answers to its 
problems, is more than made up for by the com- 
pensating fact that there seems to be no limit 
to the perfection to which plant achievements 
may be carried no impassable barrier, appar- 
ently (save time which limits us all, in every- 
thing), beyond which our experiments may 
not go. 



Nature did not make the laws; 
she limits herself to no grooves; she 
travels to no set schedule. 



Vol. 1 Bur. I 



MARVELOUS POSSIBILITIES IN 

THE IMPROVEMENT 

OF PLANTS 

GENERAL SURVEY OF SOME OF THE IMMEDIATE 
IMPROVEMENTS NEEDED. 

'"" HAVE finished making an analysis of a 
L number of your fruits," wrote a chemist, 
"and I find that tannic acid, which no one 
likes in their fruits, vegetables, nuts, or other 
food, and which prevents many people from en- 
joying raw fruit, is almost entirely absent in 
every case." 

There are other acids, however, which are 
beautifully blended with grape sugars and other 
sweet substances and flavors which make our 
fruits so delightful and so valuable for food. 
Would it be a small achievement to rebuild our 
fruits, grains and vegetables so as to add to the 
health, happiness, and advancement of the 
human race? 

Such a transformation is one which might 
easily be wrought in a few years through simple 

259 



260 LUTHER BURBANK 

selection, and serves, here, to illustrate the vast 
range of possibilities in plant improvement which 
only await willing hands and active minds to turn 
them into realization. 

Immediate possibilities for plant improvement 
outnumber the improvements which have al- 
ready been wrought, a thousand to one. 

It is planned in these books to treat of the 
possibilities of some of the plants separately, in 
connection with the description of the work which 
has already been done, since each of these im- 
provements not only suggests the road to count- 
less other improvements which one has not had 
time to take up, but indicates, in a measure, the 
method by which their accomplishment may be 
brought about. 

It may be well, at this point, however, to sur- 
vey, roughly, the range of possibilities for im- 
provement, so that, as we go along, we may have 
an appreciative eye for the better valuation of 
the things which are awaiting accomplishment. 

The elimination of tannic acid through experi- 
mentation for other purposes is but one of the 
many improvements which have been brought 
to our attention. 

Possibly as striking an illustration of this as 
could be chosen is one which made itself evident 
in the plumcot. 



MARVELOUS POSSIBILITIES 261 

So intent was I in the purpose of combining 
these two species, the plun and the apricot a 
fruit which should reflect its double parentage in 
flesh and flavor that I thought it best to ignore 
some of the incidental possibilities of such a com- 
bination. 

The cross having been made, however, much 
thought was given to the study of other new 
characters which the combination afforded. 

Some of these were recognized as being of 
little practical value, others of great importance. 
The foliage of the plumcot tree, for example, 
does not necessarily resemble either the plum or 
the apricot, being quite generally intermediate, 
but it may be noted in passing that the foliage of 
a cross or hybrid often takes on the characteris- 
tics of either one parent or the other, or may con- 
sist of intermediate leaves, or may even present 
leaves of two distinct kinds on the same indi- 
vidual plant, but often bearing a close resem- 
blance to one or the other of the parents, 
especially in the second and succeeding gen- 
erations. 

The plumcot foliage being a blend, it was not 
surprising to discover that the root of the plum- 
cot tree resembled in color neither the bright red 
of the apricot, nor the pale yellow of the plum, 
but was of an intermediate shade. 



262 LUTHER BURBANK 

Of the thousands of characteristics of the par- 
ent species as they were subjected to examina- 
tion and analysis, one of the most startling was 
found in the surface texture of the fruit itself 
one of the most novel effects, in fact, to be seen 
in nature. 

The apricot has a fine velvety skin which 
serves not only as a protection to the fruit from 
insects and from the sun's rays, but which adds 
greatly to its attractive appearance. 

Plums, on the contrary, always have a smooth 
skin, and are often overspread with a delicate 
white or bluish bloom, powdery in form and 
easily defaced by the slightest handling. This 
bloom adds a touch of delicacy and beauty 
to the fruit, suggests its freshness and in- 
tensifies the attractiveness of the colors under- 
neath. 

In the first plumcots it was noticed that many 
had a softer, more velvety skin than the apri- 
cot and that this persisted after much handling. 
Then, as the characteristics began to become 
more fixed, after several generations of plumcots 
had appeared, it was noticed that the new fruit 
not only had the attractive velvety skin of the 
apricot, but that this velvet overspread and pro- 
tected a bloom like that of the plum, giving the 
plumcot the plum's delicacy of appearance with 



MARVELOUS POSSIBILITIES 263 

the apricot's ability to stand handling without 
injury. 

When this blend of bloom and velvet was 
noted, experiments were made to determine how 
much handling it would withstand. A dozen 
plumcots were passed around from hand to hand 
many times, and then left to fully ripen and de- 
cay, the condition of the velvet bloom being 
noted from time to time. While there was a 
slight decrease in the brilliancy of the bloom, yet 
it persisted to a surprising degree, even after the 
flesh of the plumcot had decayed. 

The value of this characteristic is greater than 
might at first be supposed. Plums lose their 
bloom to a great extent, even on the tree, by 
brushing of leaves or chafing together. Wher- 
ever foliage or other fruit touches it, the bloom 
is injured or destroyed. It is of course impos- 
sible to market the plum without destroying the 
greater part of the bloom, thus giving the fruit 
a shiny appearance. In making the photographs 
in these books, in fact, it has been found difficult, 
first to find a plum fruit of any variety which 
has a perfect bloom on the tree; and second, to 
get the plum in front of the camera without de- 
facing it. Wherever a finger touches the plum, 
a mark is left, and since fruits, at best, must 
receive much handling from the orchard to the 



THE PLUM'S PERISHABLE 
BLOOM 

From this direct-color photograph 
print the result of handling plums may 
be imagined. These plums have been 
defaced merely by the swishing of the 
branches of the tree on which they 
grew. Since the bloom suggests the 
freshness of the fruit, its perishability is 
a great drawback in handling and ship- 
ping plums to the market. The plum- 
cots are not defaced by handling. 



MARVELOUS POSSIBILITIES 265 

ultimate consumer, the plum is likely to lose one 
of its most attractive charms long before its real 
freshness or flavor has begun to depreciate. 

With many of the plumcots, however, the vel- 
vety bloom remains through growing, picking, 
sorting, shipping, handling, and sale. Which 
means, of course, that the grower, the shipper 
and dealer receive a better profit, and the con- 
sumer gladly pays the extra cost, because ap- 
pearance, after all, is nearly as valuable a point 
in a fruit as size, flavor, or quality. This one im- 
provement in the plumcot greatly increases the 
earning capacity of the fruit, which is simply an- 
other evidence of the importance, in plant im- 
provement (and elsewhere), of things which, at 
first, we are too apt to regard as trifles. 

It is the seeming trifles, after all, which appear 
to have the greatest effect on prices and profits. 

Of two samples of canned asparagus one may 
command more than twice the retail price of the 
other, and also bring perhaps nearly double the 
profit to the grower, simply because of the trifle 
that one variety of asparagus holds its form and 
color through all the operations from the garden 
to the table, while the other, dark colored or 
broken in structure, presents an unappetizing 
appearance when served, and since it costs no 
more to raise the best asaparagus, after the ex- 



266 LUTHER BURBANK 

pense of a few seasons of selection has been paid 
for, what excuse can there be for producing the 
other kind? 

It would be impossible here to begin to cata- 
log the improvements which can be wrought 
improvements in size, shape, color, texture, juici- 
ness, flavor, sweetness, or chemical content of 
fruits; improvements in the appearance, tender- 
ness, taste, cooking qualities, and nutritive ele- 
ments in vegetables ; improvements in length and 
strength of fiber in cotton, flax, hemp, and in 
many other textile plants; improvements in the 
quantity and quality and color of grains; im- 
provements in amount and value of the chemical 
content of sugar beets, sorghum, coffee, tea, and 
all other plants which are raised for their ex- 
tracts; improvements in the stalks of corn, even, 
so that, though we could make it bear no more 
kernels, or no more ears, it would still yield us a 
better forage crop ; or better quality and greater 
productiveness of its special products: starch, 
gluten, oil, sugar, etc.; improvements, all of 
them, which are capable of turning losses into 
profits, and of multiplying profits, instead of 
merely adding to them by single per cents. 

Improving the yield, and consequently the 
usefulness and profit of existing plants, however, 
is but the beginning of the work before us. 



MARVELOUS POSSIBILITIES 267 

An almost equally rich field lies in saving 
plants from their own extravagances, thereby in- 
creasing the yield. 

The fruit trees of our fathers and mothers 
were shade trees in size, with all too little 
fruit. 

The ideal orchard of to-day, generally speak- 
ing, is one from which the fruit can be picked 
without the use of a ladder. Thus, already, we 
have taught fruit-bearing plants economy 
saved them the extravagance of making unneces- 
sary wood, at the expense of fruit, since it is their 
fruit, not wood, which we desire. 

The grapes of our childhood grew sparsely on 
climbing vines which covered our arbors; while 
the grapes grown for profit to-day grow thickly, 
almost solidly, on shorter, more compact vines. 
The value of the vine lies in the fruit and not in 
the wood. 

In so many different ways can we save our 
plants extravagance and increase their useful 
products by curbing their useless ones, that it 
would not be even possible to list them here. But, 
aside from these, and in the same category, there 
are countless other improvements to be wrought. 
The stoneless plum, the seedless grape, orange, 
lemon and others point the way to a new world 
of fruits in which the stony or shell-like covering 



268 LUTHER BURBANK 

of the seeds has been bred away. Wild pine- 
apple fruits are crowded with seeds, but who has 
seen seeds in our cultivated ones? Yet the pack- 
ers of pineapple in the Hawaiian Islands tell 
me that about one in a million of the cultivated 
ones are found containing large quantities of 
seed a reversion to the wild type. 

Seedless raspberries, blackberries, gooseber- 
ries, currants, with the energy saved, reinvested 
in added size or better flavor, call for some one 
to bring them about. Grapes more or less seed- 
less we have had for a hundred years or more, 
and one seedless orange has been known for half 
a century and the seedless banana has been 
known perhaps for a thousand years, while all 
wild bananas are half filled with large, black, 
hard, bulletlike seeds. Seedless figs, even 
might be produced, but these could be counted 
as no improvement, for the oily seeds of the fig 
give the fruit a part of its flavor. 

Thornless blackberries and spineless cactus 
are productions of priceless value, as is be- 
ing abundantly proven. Many other thornless 
plants are to come shortly. Why thorns at all 
in the world of useful plants, when useful plants 
no longer need them? They are as expensive 
and useless as horned cattle, which are every- 
where being replaced by hornless ones. 



MARVELOUS POSSIBILITIES 269 

Whatever plant we observe we shall see some 
waste which might be eliminated, some weakness 
which might be overcome, some extravagance 
which might be checked and all for the profit 
of producer and consumer alike, as well as the 
whole world at large. 

Still another important department of plant 
improvement lies in fitting plants to meet 
specific conditions. 

The grape growers of France, Spain, and 
California, for example, had their fair vineyards 
destroyed by a little plant root louse (Phyllox- 
era), a pest which renders the vine useless or 
kills it outright. The growers found relief 
through grafting their vines on phylloxera re- 
sistant roots which past environment had 
armored against this pest. 

When we think of the cactus, sagebrush and 
the desert euphorbia, and of the conditions 4 
which, unaided, they have withstood and the 
enemies which they have overcome, does it not 
seem as if, with our help, we should be able to 
produce new races of plants to withstand the 
boll weevil, the codling moth, and the San Jose 
scale ; and with complaints so broadcast and suc- 
cesses so marked and so many, does not the pro- 
duction of disease-and-pest-resisting varieties 
seem an important field for work? 



270 LUTHER BURBANK 

Nor are the insects and fungous diseases the 
only enemies which plants can be taught to over- 
come. Trees have been trained to bloom later 
in the season so as to avoid the late spring frosts 
which might nip their buds ; and to bear earlier, 
that their fruit may be gathered before the early 
frosts of fall have come to destroy. The gladio- 
lus has been encouraged to rearrange its blos- 
soms, shorten its stalk and thicken its petals, so 
that the hot sunshine and the wind no longer 
ruins its beauty. 

And the prune, which at times must lie on 
the ground till it is gathered or even cured, had 
the habit, here in California, of ripening about 
the time of the equinoctial rains of fall. It has 
been helped to shift its bearing season earlier, 
so that, now, when the rains come, some of the 
newer prunes have been cured and are under 
cover. 

In all of these enemies of plant life: 
insects, fungous diseases, rains, winds, frosts, 
snows, and the parching heat of the plains, 
there are opportunities for great improve- 
ment in plants, trees, grasses, grains, and 
flowers. 

Yet these enemies form the least important, 
perhaps, of the special conditions to which plants 
may be accommodated. 



MARVELOUS POSSIBILITIES 271 

The market demand, for example, is a specific 
condition which well repays any effort expended 
in transforming plants to meet. 

The grower of early cherries, early asparagus, 
early corn and every fruit and food which can 
be offered before the season of more abundant 
production commences, is rewarded with a 
better price, which means a larger profit to the 
producer. 

The early bearers, too, may be supplanted 
with those still earlier, until the extra early 
ones come soon after the extra late ones, thus 
filling out the whole year. We now have 
strawberries which, in climates where there is 
no frost severe enough to prevent, bear the year 
around. 

The Crimson Winter Rhubarb, another year- 
around bearer, is an improvement which shows 
what can be done in the way of meeting market 
demands. 

Cherries of my Early Burbank brought $3.10 
a pound wholesale, because of their sweetness 
and extreme earliness. This may give an idea 
of the profit of changing the bearing periods of 
our plants as against taking their product as 
it comes. 

Besides the market demand for fresh fruits 
and vegetables ahead of the usual time, there is 



272 LUTHER BURBANK 

an almost equally great demand in larger quan- 
tities, later on in the season, from the canners 
and for drying. 

The illustration of the asparagus which stands 
canning as against asparagus which does not, 
typifies the needs of this demand. The same 
truth applies to tree fruits and berries and vege- 
tables to everything that undergoes the pre- 
serving process. 

Some plants are more profitable when their 
bearing season is lengthened as much as possible ; 
some, as has been seen, when it is made earlier or 
later; but we faced a different condition when 
we produced the Empson pea. 

The canners wanted a very small sweet green 
pea to imitate the French one which was so much 
in demand. Quite a little problem in chemistry 
was involved. Peas half grown are sweeter than 
peas full grown, because, toward the end, their 
sugar begins to go a step further and turn into 
starch. With these demands in mind, we planted 
and selected; planted again and reselected until 
we had the desired qualities in a pea of the right 
size when half ripe. 

Still another element entered peas for can- 
ning should ripen all at one time and not strag- 
gle out over a week or two. The reason for this 
being that, if they ripen all at once, they may 



MARVELOUS POSSIBILITIES 273 

be harvested by machinery so that the cost of 
handling is cut to the minimum. 

We took the peas which we had selected for 
form, size, color, taste, content, and productive- 
ness, and out of thousands obtained perhaps a 
few hundred peas which were planted separately. 
These, then, were harvested by separately count- 
ing the pods and counting the peas, until finally 
there was combined in this selection not only the 
best of the lot, but those which ripened all at the 
same time practically on the same day. To- 
day the Burbank Empson peas form one of the* 
chief industries of a large community. 

This contract was made to be fulfilled in six 
years, but as two crops of peas can be ripened 
each season the desired production was ready and 
completed in three years. 

There are countless other requirements which 
can be equally well met little economies which 
can be taught to the plants little, as applied 
to any specific plants, but tremendous in the 
aggregate. 

The list could be extended almost endlessly; 
the skin of a plum was thickened so as to enable 
it to be shipped from Cecil Rhodes's farm in 
South Africa, by way of the Isthmus of Suez to 
England, then to New York, with some delays, 
then to California, arriving in good condition. 



274 LUTHER BURBANK 

This was one of my first efforts in producing a 
good shipping plum; even better shippers have 
been produced on my grounds and are shipped 
out of this State by the million crates annually. 

Under the head of saving a plant from its own 
extravagance might well come the large subject 
of bringing trees to early fruiting, or of greatly 
shortening the period from seed to maturity in 
shade and lumber trees. The rapid-growing 
walnut, and pineapple quince, and chestnut seed- 
lings bearing at six months from the seed stand 
forth as strong encouragement to those who 
would take up this line. 

And there is the broad subject of adapting 
plants to special localities. The hop crop of 
California, the cabbage crop near Racine, Wis- 
consin, the celery crop near Kalamazoo, the can- 
taloupe crop at Rocky Ford and Imperial Val- 
ley and the seed farms of California all of these 
bear eloquent testimony to the profit of a special- 
ty properly introduced. 

Who can say how many who are making only 
a living out of corn or wheat, simply because 
they are in corn or wheat localities, could not fit 
some special plant to their thin or worn-out soil? 

And who, seeing that some forms of plant life 
not only exist, but thrive, under the most adverse 
conditions, shall say that there is any poor land 



MARVELOUS POSSIBILITIES 275 

anywhere? Is it not the fact that poor land 
often means that the plants have been poorly 
chosen for it, or poorly adapted to it? 

These are all problems which will be treated 
in their proper places, and which offer rich 
rewards to plant improvers of skill and patience. 

So far, in mentioning some of these opportu- 
nities for plant improvement, we have referred 
only to the betterment of plants now under cul- 
tivation. 

When we remember that every useful plant 
which now grows to serve us was once a wild 
plant, and when we begin to check over the 
list of those wild plants which have not yet 
been improved, the possibilities are almost 
staggering. 

Not all plants, of course, are worth working 
with not all have within them heredities which 
could profitably be brought forth combined and 
intensified. But, as a safe comparison, it might 
be stated that the proportion between present 
useful plants and those yet wild which can be 
made useful, is at least as great as or greater 
than the proportion between the coal which has 
already been mined and the coal which is still 
stored in the ground. 

Greater, by probably a hundred times, for 
while we have depleted our coal supply, our 



276 LUTHER BURBANK 

plants have been multiplying not only in num- 
ber, but in kind and in form. 

Moreover, from our wild plants, we may not 
only obtain new products but new vigor, new 
hardiness, new adaptive powers, and endless 
other desirable new qualities for our cultivated 
plants. 

All of these things are as immediate in possi- 
bilities and consequences as transcontinental rail- 
roads were fifty years ago. All can be made to 
come about with such apparent ease that future 
generations will take them as a matter of course. 

Yet we have not touched, so far, on the most 
interesting field in plant improvement the pro- 
duction, through crossing, hybridizing, and selec- 
tion, of wholly new plants to meet entirely new 
demands. 

Who shall produce some plant and there are 
plenty of suggestions toward this end which 
shall utilize cheap land to give the world its sup- 
ply of wood pulp for paper making, the demand 
for which has already eaten up the larger part 
of our forests and is fast encroaching on 
Canada's? 

Who shall say that within twenty years there 
will not be some new plant better than flax, 
some plant which, unlike flax for this purpose, 
can be grown in the United States, to supply us 



MARVELOUS POSSIBILITIES 277 

with a fabric as cheap as cotton, but as fine and 
durable as linen? 

Who will be the one to produce a plant which 
shall yield us cheaper rubber a plant growing, 
perhaps, on the deserts, which shall make the cost 
of motor-car tires seem only an insignificant item 
in upkeep? 

And who, on those same deserts, and growing, 
perhaps, side by side, shall perfect a plant which 
can be transformed into cheap alcohol for the 
motors themselves? 

We see that the opportunities for plant im- 
provement broadly divide themselves into four 
classes. 

First, improving the quality of the product of 
existing plants. 

Second, saving plants from their own extrav- 
agance, thereby increasing their yield. 

Third, fitting plants more closely to specific 
conditions of soil, climate, and locality. 

And fourth, transforming wild plants and 
developing entirely new ones to take care of new 
wants which are growing with surprising rapidity. 

The cost and the quality of everything that we 
eat and wear depends on this work of plant im- 
provement. 

The beefsteak for which we are paying an 
ever-increasing price represents, after all, so 



278 LUTHER BURBANK 

many blades of grass, so much grain, or per- 
haps, so many slabs of cactus; while the pota- 
toes, lettuce, and coffee which go with it come 
out of the ground direct. 

Our clothing is from cotton or flax, or perhaps 
a sprinkling of wool, or from the mulberry tree 
on which the silkworm feeds. 

Our shoes and our woolens, like our steaks, re- 
solve themselves into grass. 

The mineral kingdom supplies the least of 
our needs; and the animal kingdom is wholly 
dependent on the vegetable kingdom. 

Who can predict the result when the inventive 
genius of young America is turned toward this, 
the greatest of all fields of invention, as it is now 
turned toward mechanics and electricity? This 
important line of effort would probably have been 
more enticing if patents could be obtained for 
meritorious plant inventions, but so far no pro- 
tection whatever can be extended, even though 
the new self-repeating products were worth, as 
some of them are, a thousand million dollars 
each. 



PIECING THE FRAGMENTS OF 
A MOTION-PICTURE FILM 

WE STOP TO TAKE A BACKWARD GLANCE 

>( \ X THEX you speak of environment as an 

y \ active influence," I am asked, "do you 
mean the soil, the rainfall and the 
climate?" 

Yes, I mean these, but not only these ; I mean 
also such elements of environment as the Union 
Pacific Railroad. 

I will explain. 

Go out into the woods, almost anywhere in 
the United States, and hunt up a wild plum 
tree, and you will find that it bears a poor lit- 
tle fruit with a big stone. 

The only purpose which the wild plum has in 
surrounding its seed with a fruit anyway is to 
attract man and the animals, so that they may 
carry it away from the foot of the parent tree 
and start it in new surroundings for the good 
of itself and offspring in the race for life. It 

279 



280 LUTHER BURBANK 

takes very little meat and very little in the way 
of attractive appearance to accomplish this pur- 
pose; and besides, the wild plum has to put so 
much of its vitality into stone, in order to pro- 
tect the seed within from the sharp teeth of the 
animals which carry it away, that it has little 
energy and no reasonable object left for devot- 
ing itself to still further enhanced beauty and 
flavor. 

Now, take the same wild plum after it has 
been brought under cultivation and as it grows 
in the average garden and you will find a 
transformation less stone, more meat, better 
flavor, finer aroma, more regular shape, brighter 
colors. 

This, however, represents but the first stage in 
the progress of the plum; with all this improve- 
ment the garden plum still may not be useful 
for any commercial purpose, because people 
with plum trees in their orchards are likely to 
eat the fruit off the tree, or to give it to their 
neighbors, or to cook and preserve it as soon as 
ripe. So even the cultivated garden plum may 
be perfectly satisfactory for its purpose without 
having those keeping qualities necessary to a 
commercial fruit. 

And this is the point at which the Union 
Pacific Railroad entered into its environment 



A BACKWARD GLANCE 281 

at least into the environment of the California 
plums. 

The railroad became a factor in plum im- 
provement by bringing millions of plum-hungry 
Easterners within reach by affording quick and 
economical shipping facilities where there had 
been no shipping facilities before. 

Much as the time of transcontinental travel 
was reduced, the garden plum could not with- 
stand the journey. With an eager market as an 
incentive, however, made possible through the 
railroad, we began to select plums for shipment, 
until the plum graduated from its garden en- 
vironment and became the basis of a great thriv- 
ing and constantly increasing industry. The 
railroad, by bringing customers within reach of 
those who had plums which would stand ship- 
ment, and charging as much to ship poor plums 
as good plums, encouraged selection not only for 
shipping plums, but toward a better and better 
quality of fruit which doubtless, in the absence 
of the market which the railroad provided, would 
never have been produced. 

Thus we see three important stages in the 
transformation of the plum: 

First the wild era. 

Second the garden era. 

Third the orchard and railroad era. 



282 LUTHER BURBANK 

When we stop to think of it, all of the great 
improvements in plant life have been wrought 
within the railroad era. 

Yet our plants go back, who knows how many 
tens of thousands of generations? 

It took the plum tree all of these uncounted 
ages, in which it had only wild environment, to 
produce the poor little fruit which we find grow- 
ing in the woods. 

It took only two or three short centuries of 
care and half-hearted selection to bring about the 
improvement which is evidenced in the common 
backyard plum. 

And it took less than a generation, after the 
railroads came, to work all of the real wonders 
which we see in this fruit to-day. 

L T p to two or three human generations ago, 
the plants, with their start of tens of thousands 
of generations, were abreast of or ahead of 
human needs. But human inventive genius, 
going ahead hundreds or thousands of years at 
a jump, bringing with it organization and spe- 
cialization, has changed all of that. 

In our race across the untracked plains before 
us we have outrun our plants. That is all. And, 
having outrun them, we must lend a hand to 
bring them up with us if they are to meet our 
requirements. 



A BACKWARD GLANCE 283 

Shall we content ourselves with watering our 
plants when they are dry and enriching the soil 
when it is worn out ? Shall we be satisfied merely 
to be good gardeners? 

Or shall we study the living forces within the 
plants themselves and let them teach us how to 
work real transformations? 

It is conceivable that a manufacturer of 
machinery might become successful, or even rise 
to be the foremost manufacturer in his line, with- 
out giving a moment of consideration to the 
atom structure of the iron which he works with 
never a thought of the forces which nature has 
employed in creating the substance we call iron 
ore. 

It is conceivable that one might become a good 
cook a master chef, even without the slightest 
reference to, or knowledge of, the structural for- 
mation of animal and vegetable cells. 

Or that one might succeed as a teacher of the 
young might become, even, a nation-wide au- 
thority on molding the plastic mind of youth 
without ever being assailed by the thought that 
the forbears of the nimble-minded children in his 
care, ages and ages ago, may have been swinging 
from tree to tree by their tails. 

And so, in most occupations, it has been con- 
trived for us that we deal only with present-day 



284 LUTHER BURBANK 

facts and conditions that there is little incen- 
tive, aside from general interest or wandering 
curiosity, to try to lift the veil which obscures 
our past or to peer through the fog which 
keeps us from seeing what to-morrow has in 
store. 

In plant growing, more than in any of the 
world's other industries, does the scheme of evo- 
lution and a working knowledge of nature's 
methods cease to be a theory of far-away im- 
portance and of no immediate interest and be- 
come an actual working factor, a necessary tool, 
without which it is impossible to do the day's 
work. 

Whether plant improvement be taken up as a 
science, as a profession, or as a business or 
whether it be considered merely a thing of 
general interest, an idle hour recreation there 
is ever present the need to understand nature's 
methods and her forces in order to be able to 
make use of them to guide them there always 
stares us in the face that solitary question: 

" Where and how did life start?" 

We have seen in these books color photo- 
graphs of corn as it may have grown four thou- 
sand years ago, perhaps. 

It took less than twelve seasons to carry this 
plant backward some thousands of years. 



A BACKWARD GLANCE 285 

How this plant was first taken back to the 
stage in which it was found by the American 
Indians, thus revealing the methods which they 
crudely used to improve it and how it was 
taken back beyond the Pharaohs and then back 
forty centuries before the time of man how we 
know these things to be true and how, as a result 
of these experiences we are about to see it carried 
forward by several centuries all of these things 
are reserved for a later chapter where space will 
permit the treatment which the subject deserves. 

The illustration is cited here merely as one of 
thousands, typical of plant improvement, in 
which, in order to work forward a little, we must 
think backward ages and ages. 

It is cited here to show that what is merely an 
interesting theory to the mass of the world's 
workers becomes a definite, practical, working 
necessity to the man or woman who becomes 
interested in plant improvement. 

It is cited here so that we may be helped to 
get a clearer mind picture of our viewpoint 
of that viewpoint which> after all, has enabled 
us to become a leader in a new line, the founder 
of a new art instead of remaining a nursery- 
man or gardener. 

In my viewpoint there is little that is new 
little that has not been discovered bv others 



286 LUTHER BURBANK 

little that has not been accepted by scientists 
generally little that requires explanation to 
those who simply see the same things that I 
have seen. 

I have no new theory of evolution to offer 
perhaps only a few details to add to the theories 
which have already been worked out by men of 
science. 

And I make these observations and conclu- 
sions of mine a part of this work for two reasons : 

First, because they are products not of imag- 
ination, reasoning, or any mental process but 
the practical observations and conclusions which 
have gained force and proof, year by year, in a 
lifetime of experience with plants throughout 
fifty years of continuous devotion to the subject, 
during which time I have tried more than one 
hundred thousand separate experiments on plant 
life; and, as such, represent an important phase 
of my life. 

Second, because an ever-present interest in 
evolution an ever-eager mind to peer backward 
and forward is essential not only in the prac- 
tice of plant improvement, but even to the barest 
understanding of it. 

To gain the first quick glimpse, let us liken 
the process of evolution to a moving picture as 
it is thrown on the screen. 



A BACKWARD GLANCE 287 

Imagine, for example, that some all-seeing 
camera had made a snapshot of nature's progress 
each hundred years from the time when plant 
life started in our world to the present day. 

Imagine that these progressive snapshots 
were joined together in a motion picture reel, 
and thrown in quick succession upon a screen. 

We should see, no doubt, as the picture began 
to move, a tiny living being, a simple cell, the 
chemical product, perhaps, of warm brackish 
water so small that 900 of them would have to 
be assembled together to make a speck large 
enough for our human eyes to see. 

As snapshot succeeded snapshot we should 
see that two of these microscopic simple cells in 
some way or other formed a partnership prob- 
ably finding it easier to fight the elements of 
destruction in alliance than alone. 

We should see, beyond doubt, that these part- 
nerships joined other partnerships, and as 
partnership joined partnership, and group 
joined group, these amalgamations began to have 
an object beyond mere defense that they began 
to organize for their own improvement, comfort, 
well-being, or whatever was their guiding object. 

We should see that, whereas each simple cell 
had within it all of the powers necessary to live 
its life in its own crude way, yet with the amal- 



288 LUTHER BURBANK 

gamation of the cells there came organization, 
development, improvement. 

Some of the cells in each amalgamation, let 
us say, specialize on seeing, some on locomotion, 
some on digestion. 

Thus, while each simple cell had all of these 
powers in a limited way, yet the new creature, 
as a result of specialization, could see better, 
move more readily, digest more easily, than the 
separate elements which went into it. 

And so, through the early pictures of our reel, 
there would be spread before us the development 
of the little simple cell into more and more 
complex forms of life first vegetable, then half 
vegetable-animal into everything, finally, that 
lives and grows about us to-day into us, 
ourselves. 

In an actual motion picture as it is thrown 
on the screen, it is only the quick progressive 
succession of the pictures that makes us realize 
the sense of motion. 

If we were to detach and examine a single 
film from the reel, it would show no movement. 
It would be as stationary and as fixed as a child's 
first kodak snapshot. 

In the motion picture of nature's evolution, 
the world, as we see it about us in our lifetime, 
represents but a single snapshot, detached from 



A BACKWARD GLANCE 289 

those which have preceded it and from those 
which are to succeed it. 

And so, some of us too many of us not 
confronted with the same necessity which irre- 
sistibly leads the plant student into the study of 
these forces viewing only the single, apparently 
unmoving picture before us, have concluded 
that there is no forward motion that there 
has been no evolution that there will be 
none. 

The plant student, above all others, has the 
greatest facilities at his hand for observing not 
only the details of the picture which is now on 
the screen but for gaining glimpses frag- 
mentary glimpses of pictures which have pre- 
ceded of piecing these together and of real- 
izing that all that we have and are and will be 
must be a part of this slow, sure, forward-moving 
change that unfailingly traces itself back to the 
little simple cell. 

As we go further and further into the work 
we shall begin to see the film fragments which to 
workers in other lines are obscured, unnoticed, 
unknown. 

We shall be able to observe details of the 
process carried home to us with undeniable 
conviction indisputable to any man who be- 
lieves what he actually sees which will give 

Vol. 1 Bur. J 



290 LUTHER BURBANK 

us a realistic view of the whole motion picture 
which to the world at large has always been 
denied. 

We shall find that, dealing thus with nature's 
forces at first hand, our work will inspire an 
interest beyond even the interest of creating new 
forms of life. 

And, as our work unfolds, the side lights which 
we shall see will clear up many or most of the 
doubts which are likely to take possession of us 
at the outset. 

It may be well at this point, however, to 
take space to refer to the single question most 
frequently asked by thousands of intelli- 
gent men and women who have been visitors 
here. 

This question, differing in form, as the indi- 
vidualities of the questioners differ, usually runs 
like this: 

"If we are descendants of monkeys, why are 
not the monkeys turning into men to-day?" 

Let us learn the answer to this question by 
turning to the golden-yellow California poppy, 
so-called, and the other entirely new poppies 
which we have produced from it. 

In order to make clear the truth which the 
poppies prove, it is necessary to explain the suc- 
cessive steps of the operation. 



A BACKWARD GLANCE 291 

A few thousand of the wild golden-yellow 
poppies such as cover California's hills were 
examined. 

The individuals of these resembled one another 
as closely as one rose resembles another rose on 
the same bush, or as one grape resembles another 
on the same bunch, as one pea resembles another 
in the same pod. 

Yet among those million poppies all looking 
alike to the unpracticed eye there could be 
found by a close observer nearly as many indi- 
vidual differences as could be found among as 
many human beings. 

Among those million poppies, each with its 
distinct individuality, one was found which had 
a slight tendency to break away from the Cali- 
fornia poppy family and start a separate race 
of its own. 

This same tendency could be observed among 
a million men, a million roses, a million peas, a 
million quartz crystals, or a million of any of 
nature's creations. 

Those one, or two, or three out of every million 
with tendencies to break away are sometimes 
called the freaks or "sports" of the species. 

It seems as though nature, never quite satis- 
fied with her creations, is always experimenting, 
with the hope of creating a better result yet 



292 LUTHER BURBANK 

limiting those experiments to such a small per- 
centage that the mass of the race remains un- 
changed its characteristics preserved its gen- 
eral tendencies unaffected. 

The California poppy, as it grows wild, is a 
rich golden yellow. In spite of individual dif- 
ferences, this color is the general characteristic 
of the kind. It is a fixed characteristic, dating 
back at least to the time when California, because 
of the poppy-covered hills, received its name 
the land of fire from the early Spanish navi- 
gators that ventured up and down the coast. 

Out of the billions of wild poppies that have 
grown, each million has no doubt contained its 
freaks or its "sports" its few experimental in- 
dividuals which nature has given the tendency to 
break away from the characteristics of their 
fellows. 

Yet in the history of the California poppy 
family, as far back as we can trace, none of these 
freaks or "sports" has ever achieved its object. 

Among the "sports" which we found in the 
million poppies was one with a slight streak of 
crimson on one petal ; one or two with a tendency 
toward white and one with a lemon-yellow 
color. 

Without the intervention of man, these freaks 
quite likely would have perished without off- 



A BACKWARD GLANCE 293 

spring, being submerged by those having the 
usual fixed tendency. 

But by separating them and saving their seeds, 
within a few brief seasons we were able to 
produce three new kinds of the California poppy. 

Each kind had all of the parent poppy charac- 
teristics but one. They were California poppies 
in habits, growth, shape, form, grace, texture, 
and beauty. 

Yet in color they differed from the California 
wild poppy almost as a violet differs from a 
daisy. 

One of these freaks developed into a solid 
crimson poppy, another into the pure white 
poppy, and still another into the fire-flame poppy 
all now well known. 

The details of method employed and the appli- 
cation of these methods and the underlying 
principles to the improvement of other flowers, 
fruits, trees, and useful and ornamental plants, 
will be left for later chapters. But, as an illus- 
tration, this poppy experiment brings three facts 
to view. 

First, that nature creates no absolute dupli- 
cates. 

Second, that although each of nature's cre- 
ations has its own distinctive individuality, all 
the time she takes special precautions to fix, pre- 



WHITE AND CRIMSON SIDE 
BY SIDE 

The poppy still retains many of its 
wild characteristics, particularly the 
production of great quantities of seed. 
Seeds from my experiments have been 
scattered over the grounds so that pop- 
pies are likely to spring up at any 
point. In this direct-color photograph 
print the white California poppy and 
its new crimson cousin are seen grow- 
ing wild side by side. 



A BACKWARD GLANCE 295 

serve, and make permanent the characteristics 
of each of her races or kinds best suited to their 
environment. 

Third, that there is always present in all of 
her creations the experimental tendency to break 
away from fixed characteristics to start new 
races to branch out into entirely new forms of 
development. Through our intervention in the 
case of the poppy, this tendency was crowned 
with success; in ten thousand years, perhaps, 
without intervention, the same result might pos- 
sibly have occurred. 

From the fern at the water's edge to the apple 
tree which bears us luscious fruit from the 
oyster that lies helpless in the bottom of Long 
Island Sound to the human being who rakes it 
up and eats it every different form of life 
about us may thus be traced to the experiments 
which nature is continually bringing forth in 
order to better adapt her creations to their 
environment. 

As to the question so often asked, monkeys 
are no more turning into men than golden-yellow 
poppies are turning into crimson, white or fire- 
flame poppies. 

In monkeys, as in men and poppies and 
quartz crystals there is ever present the tend- 
ency to break away from the kind, yet nature 



296 LUTHER BURBANK 

is always alert to prevent the break unless it 
demonstrates itself to be an advance, an improve- 
ment from occurring. 

She gives us, all of us, and everything indi- 
viduality, personality unfailingly, always at 
the same time preserving in each the general 
characteristics of its kind. 

Yet all the time she is creating her freaks and 
"sports" all the time she is trying new experi- 
ments most of them doomed to die unproduc- 
tive with the hope that the dozen freaks among 
a billion creations may show the way toward a 
single adaptive improvement in a race. 

In this hurried backward glance we have by 
no means gone back to the beginning of things. 
Even the moving picture of nature's course from 
the warm water cell to us, covering what seems 
an infinity of time, may be but a single stationary 
film in a still greater moving picture and that, 
too, but a part of a greater whole. 

Indeed, the further we go into our subject, 
the more we are convinced that instead of having 
followed the thread of life to its beginning, we 
have merely been following a raveling which 
leads into one of its tiny strands. 

The more we learn definitely about the process 
which we trace back to the simple cell, the more 
we are led to inquire into those other forms of 



A BACKWARD GLANCE 297 

energy into the chemical reactions into the 
vibrations which manifest themselves to us as 
sound, heat, light into electricity and those 
manifestations whose discovery is more recent, 
and whose nature is less well understood. 

The more we observe the phenomena in our 
own fields of activity, the more we realize the 
futility of trying, in a single lifetime, to explore 
infinity. 

The more content we feel, instead, to learn 
as much as we can that is useful and prac- 
tical of the single strand of life's thread which 
has to do more immediately with the thing in 
hand. 

"What do you .put into the soil to make your 
cannas so fine?" 

"How often do you take up the bulbs of your 
gladioli?" ( 

"How late do you keep your tender plants 
under glass?" 

These, and a hundred others of their kind, are 
the questions which visitors at the experiment 
farm are continually asking. 

It is not that we do not appreciate the impor- 
tance of cultivation. 

But the questioners fail to realize that our 
work has been with the insides of plants and not 
with the externals. 



298 LUTHER BURBANK 

Of the details of working method of the little 
plans that save time of the bold innovations 
which many may have dreamed, but none have 
ever dared to do; of these, in the volumes to 
come, we shall find plenty. 

And we shall find ourselves searching the 
times when things were not as they are, in order 
to obtain glimpses of things as they are to be 
and all, not from the standpoint of theory, but 
merely to help us in the very practical, the very 
useful work of developing by natural methods 
new forms of plant life better forms than she 
would produce for us unaided plants which be- 
cause of their greater productivity will help us 
lower our constantly increasing cost of living 
plants which will yield us entirely new sub- 
stances to be used in manufactures plants 
which will grow on what now are waste places 
plants which, by their better fruit, or their 
increased beauty, or their doubled yield, or their 
improved quality, will add to our individual 
pleasures and profits and to the pleasure and 
profits of the whole world. 



In order to work forward a little, 
wj must look backward through 
the ages. 



THE SHASTA DAISY 

How A TROUBLESOME WEED WAS REMADE 
INTO A BEAUTIFUL FLOWER 

HAVING, now, a broad general under- 
standing of the work of the underlying 
principles, of the methods involved, and 
of the possibilities let us see just how several 
striking transformations have been accom- 
plished. 

There are many of these productions which 
may be rated as much more important to the 
world than those described; but these have been 
selected because they reflect, better than others, 
the various ways in which methods have been 
combined to produce final, fixed results; thus 
serving to give the reader a complete exposition 
of working detail in the smallest possible space. 
We have given, for the first time, the exact 
steps which we took in producing a number of 
widely different plant transformations; together 
with some observations on life plant, animal, 
and human. 

299 



300 LUTHER BURBANK 

"White is white," said one of my gardeners, 
"and all these daisies are white. They all look 
just the same color to me. No one of them is 
pure white, but there is one that is nearer white 
than the rest." 

All the other gardeners agreed with the first 
one, and it was some time before a visitor came 
who was not of the same opinion. Person after 
person was questioned, and each one declared 
that all the daisies in the row seemed to be pure 
white in color. No one could discriminate be- 
tween them. 

But one day a well known artist visited the 
garden, and when she was shown the row of 
daisies and asked about their color, she answered 
instantly that there was one much whiter than all 
the rest ; and to my own satisfaction she indicated 
the one that all along had seemed to be whiter 
than the others. There was no question, then, 
that this plant bore flowers nearer to purity in 
whiteness than any others of all the thousands 
of daisies in the field. 

Needless to say that particular plant had been 
selected for use in future experiments, for the 
ideal in mind was a daisy that would be of the 
purest imaginable white in color. How the ideal 
was achieved after years of effort will appear 
in due course. 



THE SHASTA DAISY 301 

The daisies in question, of which the plant 
bearing the nearly white flowers was the best 
example, had been produced by several years of 
experimentation which had commenced with the 
cultivation of the common roadside weed famil- 
iar to everyone in the East as the oxeye daisy, 
and known to the botanist as Chrysanthemum 
leucanthemum. This plant, which grows in 
such profusion throughout the East as to be 
considered a pest by the farmer, was not to 
be found in California until these experiments 
were begun. 

My admiration for the plant was chiefly as a 
souvenir of boyhood, days. But I soon con- 
ceived the idea of bettering it, for it had certain 
qualities that seemed to suggest undeveloped 
possibilities. 

In the countryside of New England, the 
oxeye, as everyone knows, is a very hardy 
plant and a persistent bloomer. Its very 
abundance has denied it general recognition, 
yet it is not without its claims to beauty. 
But it did not greatly improve or very 
notably change its appearance during the 
first few seasons of its cultivation in Cali- 
fornia; nor indeed until after I had given it 
a new impetus by hybridizing it with an allied 
species. 



THE SHASTA DAISY 

The Shasta Daisy (Chrysanthemum 
hybridum) is probably the most popu- 
lar flower introduced during the past 
century. It is grown in all parts of the 
earth and yields its graceful, snow- 
white blossoms in abundance with little 
care or culture. Everybody now knows 
the Shasta Daisy. It has taken on 
many interesting new forms of late. 



THE SHASTA DAISY 303 

MATING THE OXEYES 

The plant with which the cross was made was 
a much larger and more robust species of daisy 
imported from Europe, where it is known collo- 
quially as the Michaelmas daisy, although the 
botanist gives it a distinct name, in recognition 
of its dissimilar appearance, calling it Chrysan- 
themum maximum. There is also a Continental 
daisy, by some botanists considered as a distinct 
species and named Chrysanthemum lacustre, 
which is closely similar to the British species, 
and of this seeds were secured from a German 
firm. 

Both these plants have larger flowers than the 
American daisy, but are far inferior to it in grace 
of form and especially abundance of bloom. 
The plants have a coarse, weedy appearance, 
with numerous unsightly leaves upon their 
flower stalks, whereas the stalk of the American 
daisy is usually leafless. 

Notwithstanding the rather coarse appear- 
ance of the European oxeyes, I determined to 
hybridize them with the American species, in the 
expectation of producing a plant that would 
combine the larger flowers of the European with 
the grace, abundant flowers, and early blooming 
qualities of the American daisy. The cross was 



304 LUTHER BURBANK 

first made with the English daisy, C. maximum, 
by taking pollen from this flower to fertilize the 
best specimens of the American daisy that I had 
hitherto been able to produce. 

When the seeds thus produced were sown next 
season and the plants came to blooming time, it 
was at once evident that there was marked 
improvement. Some of the flowers appeared 
earlier even than those of the American daisy; 
they were very numerous, and were larger in size 
than the flowers of either parent. But all the 
flowers had a yellowish tinge, unnoticed by the 
average observer, but visible to a sharp eye on 
close inspection. And this tendency to a green- 
ish yellowness in color was not at all to my liking. 

Further improvement was attempted by cross- 
ing the hybrid plant with the German daisy just 
referred to. A slight improvement was noticed, 
but the changes were not very marked. 

By selecting the best specimens of the hybrid, 
which now had a triple parentage, I had secured, 
in the course of five or six years, a daisy which 
was very obviously superior to any one of the 
original forms as to size and beauty of flower, 
and fully the equal of any of them in ruggedness 
and prolific blooming. 

But the flowers were still disappointing in that 
they lacked that quality of crystal whiteness 



THE SHASTA DAISY 305 

which was to be one of the chief charms of 
my ideal daisy. So year by year the rows of 
daisies were inspected in quest of a plant bearing 
blooms whiter than the rest; and seeds were 
selected only from the prize plants. 

The daisy spreads constantly, and one clump 
will, if carefully divided, presently supply a 
garden. But of course each plant grown from 
the same plant is precisely like the parent, and 
while a large number of daisies were secured 
that combined approximate whiteness with all 
the other good qualities sought, yet the purest of 
them all did not appear to be unqualifiedly 
white. 

And when my own judgment was confirmed 
by the decision of the artist, the determination 
was made to seek some new method of further 
improvement that should erase the last trace of 
offending shade. 

As a means to achieve this end, I learned of 
another, the Asiatic daisy known to the botanist 
as Chrysanthemum nipponicum; and presently 
obtained the seed of this plant from Japan. 

AID FROM JAPAN 

This Japanese daisy was in most respects in- 
ferior to the original American oxeye with 
which these experiments had started. It is a 



306 LUTHER BURBANK 

rather coarse plant, with objectionable leafy 
stalk, and a flower so small and inconspicuous 
that it would attract little attention and would 
scarcely be regarded by anyone as a desirable 
acquisition for the garden. But the flower had 
one quality that appealed to me it was pure 
white. 

Needless to say, no time was lost, once these 
plants were in bloom, in crossing the best of the 
hybrid daisies with pollen from the flowers of 
their Japanese cousin. 

The first results were not wholly reassuring. 
But in a subsequent season, among innumerable 
seedlings from this union, one was found at last 
with flowers as beautifully white as those of the 
Japanese, and larger than the largest of those 
that the hybrid plants had hitherto produced. 
Moreover the plant on which this flower grew 
revealed the gracefulness of the American plant, 
and in due course was shown to have the hardy 
vigor of all the other species. 

From this remarkable plant, with its combined 
heritage of four ancestral strains from three 
continents, thousands of seedlings were raised 
each year for the five or six ensuing seasons, the 
best individuals being selected and the others 
destroyed according to my custom, until at last 
the really wonderful flower that has since become 



THE SHASTA DAISY 307 

known to the whole world as the Shasta Daisy 
was produced. 

Moreover I had a flower that excelled my 
utmost expectations as to size, grace and abun- 
dant blooming qualities ; a blossom from four to 
seven inches in diameter, with a greatly increased 
number of ray flowers of crystal whiteness, and 
with flower stem tall and devoid of unsightly 
leaves ; a plant at once graceful enough to please 
the eye and hardy enough to thrive in any soil; 
a plant moreover of such thrifty growth that it 
reached its blooming time in its first season from 
seed, although none of its ancestors bloomed 
until the second season; and of such quality of 
prolificness that it continues to bloom almost 
throughout the year in California, and for a long 
season even in colder climates. 

CONFLICTING TENDENCIES 

The Shasta Daisy, sprung thus magically 
yet not without years of coaxing from this 
curiously mixed ancestry, exceeded my utmost 
expectations in its combination of desirable 
qualities. I can hardly say, however, that the 
result achieved was a surprise; for my experi- 
ence with hundreds of other species had led me to 
anticipate, at least in a general way, the trans- 
formations that might be effected through such 



THE SHASTA DAISY AND TWO 
OF ITS RELATIVES 

The upper flower is a form of the 
Shasta Daisy slightly different from 
that shown on a preceding page. At 
the left is shown a newer double form, 
and at the right its New England 
parent, all reduced one-half. 



THE SHASTA DAISY 309 

a mingling of different ancestral strains as had 
been brought about. 

There was every reason to expect, while 
hybridizing the American and European ox- 
eyes, that a plant would ultimately be produced 
that would combine in various degrees all the 
qualities of each parent form. By selecting for 
preservation only those that combined the de- 
sirable qualities and destroying those that re- 
vealed the undesirable ones, a fixed, persistent 
hybrid race that very obviously excelled either 
one of its parent forms was produced. 

Nor is there, perhaps, anything very mystify- 
ing about this result, for the simpler facts of the 
hereditary transmission of ancestral traits are 
now matters of common knowledge and of every- 
day observation. 

No one is surprised for example, to see a child 
that resembles one parent as to stature, let us 
say, and the other as to color of hair and eyes. 

So a hybrid daisy combining in full measure 
the best qualities of the European and the Amer- 
ican oxeyes, as did my first hybrid race, perhaps 
does not seem an anomalous product, although 
certainly not without interest, in view of the 
fact that its parent stocks are regarded by many 
botanists as constituting at least two distinct 
species. 



310 LUTHER BURBANK 

But the final cross, in which the Japanese 
plant with its small flowers, inferior in every- 
thing except lack of color, was brought into the 
coalition, calls for explanation. A general im- 
pression has long prevailed that a hybrid race 
whether of animals or of plants is likely to be 
more or less intermediate between the parent 
races ; so perhaps the common expectation would 
have been that the cross between the new hybrid 
race of daisies and the obscure Japanese plant 
would result in a hybrid with medium-sized 
flowers at best, and, except possibly in the matter 
of whiteness of blossom, an all round inferiority 
to the best plants that I had developed. 

But, in reality, there appeared the beautiful 
mammoth Shasta, superlative in all its qualities, 
surpassing in every respect each and all of the 
four parent stocks from which it sprang. 

This apparently paradoxical result calls for 
explanation. The explanation is found, so far 
as we can explain the mysteries of life processes 
at all, in the fact that by bringing together racial 
strains differing so widely a result is produced 
that may be described as a conflict of hereditary 
tendencies. And out of this conflict comes a 
great tendency to variation. 

The reasons for this are relatively simple. 
Heredity, after all, may be described as the sum 



THE SHASTA DAISY 311 

of past environments. The traits and tendencies 
that we transmit to our children are traits and 
tendencies that have been built into the organ- 
isms of our ancestors through their age-long 
contact with varying environmental conditions. 

The American oxeye daisy, through long gen- 
erations of growth under the specific climatic 
conditions of New England, had developed 
certain traits that peculiarly adapted it to life 
in that region. 

Similarly the European daisy had developed 
a different set of traits under the diverse condi- 
tions of soil and climate of Europe. 

And in the third place, the Japanese daisy had 
developed yet more divergent traits under the 
conditions of life in far away Japan, because 
these conditions were not only more widely dif- 
ferent from the conditions of Europe and 
America than these are from each other, but 
also because the Japanese plant came of a race 
that had in all probability separated from the 
original parent stock of all the daisies at a time 
much more remote than the time at which the 
European and American daisies were separated. 

THE PLANT AS A CAMERA 

To make the meaning of this quite clear, we 
must recall that a given organism say in this 



312 LUTHER BURBANK 

case a given stock of daisies is at all times sub- 
ject to the unceasing influence of the conditions 
of life in the midst of which it exists. The whole 
series of influences which we describe as the envi- 
ronment is perpetually stamping its imprint on 
the organism somewhat as the vibrations of light 
stamp their influence on a photographic plate. 

Indeed, as I conceive it, the plant is in effect a 
photographic plate which is constantly receiving 
impressions from the environing world. 

And the traits and tendencies of the plant that 
are developed in response to these impinging 
forces of the environment are further compara- 
ble to the image of the photographic plate in that 
they have a greater or less degree of perma- 
nency according to the length of time during 
which they were exposed to the image-forming 
conditions. 

If you expose a photographic plate in a mod- 
erately dim light, let us say, for the thousandth 
part of a second, you secure only a very thin 
and vague negative. But if, without shifting the 
scene or the focus of the camera, you repeat 
the exposure again and again, each time for only 
the thousandth of a second, you will ultimately 
pile up on the negative a succession of impres- 
sions, each like all the rest, that result in the pro- 
duction of a strong, sharp negative. 



THE SHASTA DAISY 313 

But if in making the successive exposures, you 
were to shift the position of the camera each time, 
changing the scene, you would build up a nega- 
tive covered with faint images that overlap in 
such a way as to make a blurred and unmean- 
ing picture. 

And so it is with the plant. Each hour of its 
life there come to it certain chemicals from the 
soil, certain influences of heat and moisture from 
the atmosphere, that are in effect vibrations 
beating on its protoplasmic life substance and 
making infinitesimal but all-important changes 
in its intimate structure. The amount of change 
thus produced in a day or a year, or, under 
natural conditions, perhaps in a century or in a 
millennium, would be slight, for the lifetime of 
races and plants is to be measured not in these 
small units, but in geological eras. 

Nevertheless, the influence of a relatively brief 
period must make an infinitesimal change, com- 
parable to the thousandth-second exposure of the 
negative. 

And when a plant remains century after cen- 
tury in the same environment, receiving genera- 
tion after generation the same influences from 
the soil and atmosphere, the stamp of these in- 
fluences on its organic structure becomes more 
and more fixed and the hereditary influence 



SHASTA DAISIES CURIOUS 
TUBULAR RAY FLOWERS 

We have learned through observa- 
tion of many examples that when a 
flower or plant once begins to vary, it 
may continue to vary almost indefi- 
nitely. Here is an illustration of a new 
departure on the part of the Shasta 
Daisy, in which the petals take on a 
very curious form. It has interest as a 
freak rather than because of its beauty, 
but the variety is worthy of attention, 
to see what may be its further variation 
in this direction. 



THE SHASTA DAISY 315 

through which these conditions are transmitted 
to its descendants becomes more and more nota- 
ble and pronounced. 

So it is that a plant that has lived for count- 
less generations in Japan has acquired a pro- 
found heredity tending to transmit a particular 
set of qualities; and when we hybridize that 
plant with another plant that has similarly 
gained its hereditary tendencies through age- 
long residence in Europe, we bring together two 
conflicting streams that must fight against each 
other and strangely disturb the otherwise equa- 
ble current of hereditary transmission. 

Long experience with the hybrids of other 
species of plants had taught me this, and hence 
it was that I expected to bring about a notable 
upheaval in the hereditary traits of my daisies 
by bringing the pollen of a Japanese plant to 
the stigmas of my hybrid European and Ameri- 
can oxeyes. That my expectations were real- 
ized, and more than realized, is matter of record 
of which the present Shasta Daisy gives most 
tangible proof. 

We shall see the same thing illustrated over 
and over again in our subsequent studies. 

In offering this explanation of the extraordi- 
nary conflict of tendencies, with its resulting new 
and strange combination of qualities that re- 



316 LUTHER BURBANK 

suited from the mixing of the various strains of 
daisies, it will be clear that I am assuming that 
the different ancestral races were all evolution- 
ary products that owed their special traits of 
stem and leaf and flower to the joint influence 
of heredity and environment. 

I am assuming that there was a time in the 
remote past when all daisies had a common 
ancestral stock very different from any existing 
race of daisies. 

TOURING THE WORLD 

The descendants of that ancestral stock spread 
from the geographical seat of its origin which 
may perhaps have been central Asia in all direc- 
tions. In the course of uncounted centuries, and 
along channels that are no longer traceable, the 
daughter races ultimately made their way to op- 
posite sides of the world. Some now found them- 
selves in Europe, some in America, some in Japan. 

Thousands of years had elapsed since the long 
migration began; yet so persistent is the power 
of remote heredity that the daisies of Europe and 
America and Japan even now show numerous 
traits of resemblance and proof of their common 
origin that lead the botanist to classify them in 
the same genus. But, on the other hand, these 
races show differences of detail as to stem and 



THE SHASTA DAISY 317 

leaf and flower and habit which entitle them to 
rank as different species. 

As the likenesses between the different daisies 
are the tokens of their remote common origin and 
evidences of the power of heredity, so their 
specific differences betoken the influences of the 
different environment in which they have lived 
since they took divergent courses. 

The Japanese daisy is different from the Ger- 
man daisy because the sum total of environ- 
ment influences to which it has been subjected 
in the past few thousand years is different from 
the sum total of influences to which the German 
daisy has been subjected. Not merely differ- 
ences due to the soil and climate of Japan and 
Germany to-day, but cumulative differences due 
to ancestral environments all along the line of 
the migration that led one branch of the race of 
daisies eastward across Asia and the other branch 
westward across Europe. ' 

ARE ACQUIRED TRAITS TRANSMITTED? 

But all this implies that the imprint of 
the successive environments was in each case 
an influence transmitted to the offspring; and 
this is precisely what I mean to imply. 

To me it seems quite clear that the observed 
divergences between the European and the Jap- 



318 LUTHER BURBANK 

anese daisy are to be explained precisely in this 
way. I know of no other explanation that has 
any semblance of plausibility. 

It is *my personal belief that every trait ac- 
quired by any organism through the influence 
of its environment becomes a part of the condi- 
tion of the organism that tends to reproduce it- 
self through inheritance. 

In other words I entertain no doubt that all 
acquired traits of every kind are transmissible as 
more or less infinitesimal tendencies to the off- 
spring of the organism. 

But it would not do to dismiss the subject 
without adverting to the fact that there are many 
biologists who dispute the possibility of the 
transmission of acquired traits. Indeed, one of 
the most ardent controversies of recent years has 
had to do with that point; and doubtless many 
readers who are not biologists have had their at- 
tention called to this controversy and perhaps 
have received assurance that traits acquired by 
an individual organism are not transmitted. 

I shall not here enter into any details of the 
controversy, although doubtless we shall have 
occasion to revert to it. But it is well to clarify 
the subject in the mind of the reader here at the 
outset, by pointing out that this controversy, like 
a good many others, is concerned with unessen- 



THE SHASTA DAISY 319 

tial details, sometimes even with the mere jug- 
gling of words, rather than with essentials. 

As to the broad final analysis of the subject 
in its remoter bearings, all biologists are agreed. 

There is no student of the subject speaking 
with any authority to-day, who doubts that all 
animal and vegetable forms have been produced 
through evolution, and it requires but the slight- 
est consideration of the subject to make it clear 
that Herbert Spencer was right when he said 
that no one can be an evolutionist who does not 
believe that new traits somewhere and somehow 
acquired can be transmitted. 

Otherwise there could be no change whatever 
in any organism from generation to generation 
or from age to age : in a word, there would be no 
evolution. 

The point in dispute, then, is not whether any 
trait and modification of structure, due to the 
influence of environment, is transmissible, but 
only as to whether environmental influences that 
affect the body only and not the germ plasm of 
the individual are transmissible. But when we 
reflect that the germ plasm is part and parcel 
of the organism, it seems fairly clear that this 
is a distinction without a real difference. 

As Professor Coulter has recently said, it is 
largely a matter of definition. 



A BEAUTIFUL LACINIATED 
TYPE 

The flowers shown above, selected 
from some of my Shasta experiments, 
have more the appearance of the Chi- 
nese chrysanthemum., almost, than of 
the ordinary Shasta Daisy. It mil be 
noted that the flower at the lower left 
gives evidence of doubleness to such an 
extent that the center has become fully 
double. Notice the laciniated petals. 



THE SHASTA DAISY 321 

We shall have occasion to discuss this phase 
of heredity more fully in another connection. In 
the meantime, for our present purpose, it suffices 
to recall that biologists of every school will ad- 
mit the force of the general statement that 
heredity is the sum of past environments, and 
to make the specific application that our Jap- 
anese and our English and American daisies are 
different because long generations of their an- 
cestors have lived in different geographical ter- 
ritories and therefore have been subject to diverse 
environing conditions. 

In a word, then, the Shasta Daisy which 
stands to-day as virtually a new creation, so 
widely different from any other plant that no 
botanist would hesitate to describe it as a new 
species, owes its existence to the bringing to- 
gether of conflicting hereditary tendencies that 
epitomize the ancestral experiences gained in 
widely separated geographical territories. 

Without the aid of man, the plants that had 
found final refuge in Europe and America and 
Japan, respectively, would never have been 
brought in contact, and so the combination of 
traits that built up the Shasta Daisy would never 
have been produced. 

In that sense, then, artificial selection created 
the Shasta Daisy, but the forces evoked were 



Vol. 1 Bur. K 



322 LUTHER BURBANK 

those that nature provided, and the entire course 
of my experiments might be likened to an ab- 
breviated transcript of the processes of natural 
selection through which species everywhere have 
been created, and are to-day still being created, 
in the world at large. 

NEW RACES OF SHASTAS 

Once the divergent traits of these various 
strains had been intermingled, the conflict set up 
was sure to persist generation after generation. 

Each individual hereditary trait, even though 
suppressed in a single generation by the prepo- 
tency of some opposing trait, strives for a hear- 
ing and tends to reappear in some subsequent 
generation. 

So the plant developer, by keenly scrutinizing 
each seedling, will observe that no two plants of 
his hybrid crop are absolutely identical; and by 
selecting and cultivating one divergent strain or 
another, he may bring to the surface and further 
develop traits that had long been subordinated. 

Seizing on these, I was enabled, in the course 
of ensuing years, to develop various races of the 
Shasta, some of which were so very different that 
they have been given individual names. The 
Alaska, for example, has even larger and more 
numerous blossoms than the original Shasta, 



THE SHASTA DAISY 323 

with longer and stronger stems and more vigor- 
ous and hardy growth. The Westralia has blos- 
soms of even greater size, and exceptionally 
long, strong, and graceful stems, and the Cali- 
fornia has a slightly smaller flower, but produced 
in great profusion; and its blossoms, instead of 
being snowy white like those of the other races, 
are bright lemon yellow on first opening. 

Moreover the enhanced vitality due to cross- 
breeding and the mingling of different ancestral 
strains, was evidenced presently in a tendency to 
the production not merely of large blossoms, but 
of blossoms having an increased number of ray 
flowers. 

The daisy is a composite flower, and the petal- 
like leaves that give it chief beauty are not really 
petals, but are technically spoken of as rays. The 
flowers proper, individually small and inconspic- 
uous, are grouped at the center of the circling 
rays. 

In all the original species the ray flowers con- 
stitute a single row. But the hybrids began al- 
most from the first to show an increased number 
of longer and wider ray flowers, some of which 
overlapped their neighbors. 

By sowing seed from flowers showing this 
tendency, after a few generations a strain of 
plants was developed in which the blossoms were 



324 LUTHER BURBANK 

characterized by two rows of ray flowers instead 
of one. Continuing the selection, flowers were 
secured in successive generations having still 
wider and longer rays and increased numbers of 
rows, until finally handsome double-flowered va- 
rieties were produced. 

Aberrant forms were also produced showing 
long tubular ray flowers and others having the 
rays fimbriated or divided at the tip. 

And all these divergent and seemingly differ- 
ent types of flowers, it will be understood, have 
the same remote ancestry, and represent the 
bringing to the surface the segregation and re- 
combination and intensification of diverse sets 
of ancestral traits that had long been submerged. 

It is certain that no plant precisely like the 
Shasta Daisy or any one of its varieties ever 
existed until developed here in my gardens at 
Santa Rosa. 



/ have never entertained a doubt 
as to the transmissibility of ac- 
quired characters and tendencies. 



THE WHITE BLACKBERRY 

How A COLOR TRANSFORMATION WAS 
BROUGHT ABOUT 

TO SPEAK of white blackbirds or of white 
blackberries is to employ an obvious contra- 
diction of terms. Yet we all know that now 
and again a blackbird does appear that is pure 
white. And visitors to my experiment gardens 
during the past twenty years can testify that the 
white blackberry is something more than an oc- 
casional product that it is, in short, a fully es- 
tablished and highly productive variety of fruit. 
There is no record of anyone having ever seen 
a truly white blackberry until this anomalous 
fruit was produced. 

Nevertheless it should be explained at the 
outset that the berry with the aid of which I de- 
veloped the new fruit was called a white black- 
berry. It was a berry found growing wild in 
New Jersey, and introduced as a garden novelty, 
with no pretense to value as a table fruit, by Mr. 
T. J. Lovett. He called ihe berry "Crystal 

325 



326 LUTHER BURBANK 

White," but this was very obviously a misnomer 
as the fruit itself was never white, but of a dull 
brownish yellow. It has as little pretension to 
beauty as to size or excellence of flavor, and was 
introduced simply as a curiosity. 

When a white blackbird appears in a flock, it 
is usually a pure albino. It may perhaps be re- 
garded as a pathological specimen, in which, for 
some unknown reason, the pigment that normally 
colors the feathers of birds is altogether lacking. 

It is not unlikely that the original so-called 
white blackberry was also an albino of this 
pathological type. But if so, hybridization had 
produced a mongrel race before the plant was 
discovered by man, or at least before any record 
was made of its discovery; for, as just noted, the 
berry introduced by Mr. Lovett could be termed 
white only by courtesy. 

Nevertheless the berry differed very markedly 
from the normal blackberry, which, as everyone 
knows, is of a glossy blackness when ripe. So 
my interest in the anomalous fruit was at once 
aroused, and I sent for some specimens for ex- 
perimental purposes soon after its introduction, 
believing that it might offer possibilities of im- 
provement. 

Making use of the principles I have found suc- 
cessful with other plants, my first thought was to 



THE WHITE BLACKBERRY 327 

hybridize the brownish white berry with some 
allied species in order to bring out the tendency 
to variation and thus afford material for selective 
breeding. 

CREATING A REALLY WHITE BLACKBERRY 

The first cross effected was with the Lawton 
blackberry, using pollen from the Lawton berry. 
The Lawton is known to be very prepotent; it is 
of a very fixed race and will reproduce itself 
from seed almost exactly, which is not true of 
most cultivated fruits. Its seedlings often seem 
uninfluenced when grown from seed pollinated 
by other varieties. 

It was to be expected, therefore, that the cross 
between the Lawton and the "white" berry would 
result in producing all black stock closely resem- 
bling the Lawton; and such was indeed the re- 
sult. 

But the Lawton also imparts its good qualities 
to hybrids when its pollen is used to fertilize the 
flowers of other varieties. As a general rule, it is 
my experience that it makes no difference which 
way a cross is effected between two species of 
plants. The pollen conveys the hereditary 
tendencies actively, and so-called reciprocal 
crosses usually produce seedlings of the same 
character. 



328 LUTHER BURBANK 

That is to say, it usually seems to make no 
practical difference whether you take pollen from 
flower A to fertilize flower B, or pollen from 
flower B to fertilize flower A. 

This observation, which was first made by the 
early hybridizers of plants more than a century 
ago notably by Kolreuter and by Von Gartner 
is fully confirmed by my own observations on 
many hundreds of species. Nevertheless, it occa- 
sionally happens that the plant experimenter 
gains some advantage by using one cross rather 
than the other. In the present case it seemed 
that by using the Lawton as the pollenizing 
flower, and growing berries on the brownish 
white species, a race was produced with a more 
pronounced tendency to vary. 

Still the plants that grew from seed thus pro- 
duced bore only black berries in the first genera- 
tion, just as when the cross was made the other 
way. It thus appeared that the prepotency of 
the Lawton manifested itself with full force and 
certainty whether it was used as the staminate or 
as the pistillate flower. 

When the flowers of this first filial generation 
were interbred, however, the seed thus produced 
proved its mixed heritage by growing into some 
very strange forms of vine. One of these was a 
blackberry that bloomed and fruited all the year. 



THE WHITE BLACKBERRY 329 

This individual bush, instead of dying down like 
others, kept growing at the top like a vine or tree, 
anc when it was two or three years old it was so 
tall that a stepladder was required to reach the 
fruit. Its berries, how r ever, were rather small, 
soft, and jet black in color. 

This plant, then, was an interesting anomaly, 
but it gave no aid in the quest of a white black- 
berry. 

But there were other vines of this second filial 
generation grandchildren of the Lawton and 
the original "Crystal White" that showed a 
tendency to vary in the color of their fruit, this 
being in some cases yellowish white. Of course 
these bushes were selected for further experi- 
ment. Some were cross-fertilized and the seed 
preserved. 

The vines that grew from this seed in the next 
season gave early indications of possessing varied 
qualities. It is often to be observed that a vine 
which will ultimately produce berries of a light 
color lacks pigment in its stem, and is greenish or 
amber in color, whereas the stem of a vine that is 
to produce black berries is dark brown or purple. 
A few of the blackberry vines of the third gen- 
eration showed this light color ; and in due course, 
when they came to the fruiting age, they put 
forth heavy crops of clear white berries of such 



THE CRYSTAL WHITE 
SO CALLED 

Some thirty years ago we learned 
that a wild blackberry of New Jersey 
pictured opposite, lighter in color than 
any other blackberry, had been intro- 
duced as a garden novelty under 
the name Crystal White. Although 
lighter than any other blackberry, it 
was of a muddy brown color, as can be 
seen from the photograph. The berries 
were small and of poor flavor. This 
wild berry, however, was the first step 
in the production of the new varieties 
of the true white blackberries. 



THE WHITE BLACKBERRY 331 

transparency that the seeds, though unusually 
small, could readily be seen through the trans- 
lucent pulp. 

These were doubtless the first truly white 
blackberries of which there is any record. But 
there were only four or five bushes bearing these 
white berries in an entire generation comprising 
several hundred individual bushes, all having pre- 
cisely the same ancestry. 

From among the four or five bushes the one 
showing a combination of the best qualities was 
selected and multiplied, until its descendants con- 
stituted a race of white blackberries that breeds 
absolutely true as regards the white fruit. 

Now BREEDS TRUE FROM SEED 

The descendants of this particular bush were 
widely scattered and passed out of my control. 
But subsequently, from the same stock, I de- 
veloped other races, and finally perfected, merely 
by selection and interbreeding from this same 
stock, a race of white blackberries that breeds 
true from the seed, showing no tendency what- 
ever to revert to the black grandparental type. 

This is, in short, a fruit which if found in the 
state of nature would unhesitatingly be pro- 
nounced a distinct species. Its fruit is not only 
snowy white in color, but large and luscious, com- 



332 LUTHER BURBAXK 

parable in the latter respect to the Lawton berry 
which was one of its ancestors. 

"Was there ever in nature a berry just like 
this?" a visitor asked me. 

Probably not; but there was a small white 
berry and a large luscious black one, and I have 
brought the best qualities of each together in a 
new combination. 

THE ANOMALY EXPLAINED 

Reviewing briefly the history just outlined, it 
appears that the new white blackberry had for 
grandparents a large and luscious jet black berry 
known as the Lawton blackberry and a small ill- 
flavored fruit of a yellowish brown color. The 
descendant has inherited the size and lusciousness 
of its black ancestor, and this seems not alto- 
gether anomalous. But how shall we account for 
the fact that it is pure white in color, whereas its 
Alleged white ancestor was not really white at all? 

The attempt to answer that question brings 
us face to face with some of the most curious 
facts and theories of heredity. We are bound to 
account for the white blackberry in accordance 
with the laws of heredity, yet at first blush its 
dazzling whiteness seems to bid defiance to these 
laws, for we can show no recognized white an- 
cestor in explanation. 



THE WHITE BLACKBERRY 333 

This whole matter is so simple, however, that 
anyone can see the cause of this unusual white- 
ness. All plant breeders realize that any quality 
can be intensified to almost any extent by care- 
ful and persistent selection. 

There is, of course, no other very plausible ex- 
planation available of the origin of the anomalous 
berry. White is not a favorite color either among 
animals or among vegetables. Except in Arctic 
regions it is very rare indeed to find an unpig- 
mented animal or bird, and white fruits are al- 
most equally unusual. 

In the case of animals and birds, it is not diffi- 
cult to explain the avoidance of white furs and 
feathers. A white bird, for example, is obviously 
very conspicuous, and thus is much more open to 
the attacks of its enemies than a bird of some 
color that blends with its surroundings. So we 
find that there is no small bird of the Northern 
Hemisphere, with the single exception of the 
snow bunting, which normally dresses wholly in 
white. The exception in the case of the snow 
bunting is obviously explained by the habits of 
the bird itself. 

And even this bird assumes a brownish coat in 
the summer. 

There are a few large waterfowl, notably the 
pelican and certain herons that wear snowy white 



334 LUTHER BURBANK 

plumage habitually throughout the year. But 
these are birds of predacious habits that are 
little subject to the attacks of enemies, and it 
has been shown that the white color, or bluish 
white, tends to make the birds inconspicuous 
from the viewpoint of the fish that are their 
prey. 

So in the case of the tiny snow bunting and of 
pelicans and herons, the white color of the plum- 
age is seen to be advantageous to its wearer and 
hence is easily explained according to the prin- 
ciple of natural selection. The same is true of 
the white plumage assumed by those species of 
grouse and ptarmigan that winter in the Arctic 
or sub- Arctic regions; and contrariwise, the pig- 
mented coats of the vast majority of the birds 
and animals of temperate zones are accounted for 
on the same principle. 

But just why the fruits of plants should almost 
universally be pigmented seems at first not quite 
so clear. It is ordinarily supposed to be advan- 
tageous for a plant to have its fruit made visible 
to the birds and animals, that the aid of these 
creatures may be gained in disseminating the 
seed. And it must be obvious that a white black- 
berry would be as conspicuous in the woodlands 
where this vine grows as are the jet black berries 
of the ordinary type. 



THE WHITE BLACKBERRY 335 

Why, then, you ask, fras not natural selection 
developed a race of white blackberries? 

I am not sure that anyone can give an ade- 
quate answer. Perhaps it is desirable to have 
the seeds of a plant protected from the rays of 
the sun, particularly from those ultra-violet rays 
which are known to have great power in produc- 
ing chemical changes. Recent studies of the 
short waves of light beyond the violet end of the 
spectrum show that they have strong germicidal 
power. 

It will be recalled that the celebrated Danish 
physician Dr. Finsen developed a treatment of 
local tubercular affections based on the principle 
that ultra-violet light destroys the disease germs. 
And most readers have heard of Dr. Wood- 
ward's theory that very bright light is detri- 
mental to all living organisms. 

Possibly too much sunlight might have a dele- 
terious effect on the seeds of such a plant as the 
blackberry. Indeed, the fact that the berry 
quickly develops pigments under ordinary con- 
ditions, and develops them much earlier than the 
stage at which it is desirable to have the fruit 
eaten by birds, suggests that this pigment is 
protective to the fruit itself in addition to its 
function of making the fruit attractive to the 
bird. 



336 LUTHER BURBANK 

But be the explanation what it may, the fact 
remains that very few fruits in a state of nature 
are white; and no one needs to be told that fruits 
of the many tribes of blackberries, with the single 
exception of the one under present discussion, are 
of a color fully to justify the name they bear. 
Yet the experiment in breeding just recorded 
proves that, at least under the conditions of arti- 
ficial selection, a race of berries may be devel- 
oped which, though having the flavor and con- 
tour of the blackberry, is as far as possible from 
black in color. 

The fact that this race of white berries was 
developed in the third generation from parents 
one of which is a jet black fruit and the other a 
fruit of a brownish tint, seems at first glance to 
give challenge to the laws of heredity. 

ATAVISM AND UNIT CHARACTERS 

Even though we should assume that a remote 
ancestor of our newly developed white black- 
berry might have been a pure albino, the case 
still seems mysterious. Cases of reversion to the 
type of a remote ancestor have been observed 
from time to time by all breeders of animals and 
by students of human heredity, and it has been 
customary to explain such cases of reversion, or 
at least to label them with the word "atavism." 



THE WHITE BLACKBERRY 337 

If tills word be taken to imply that all traits 
and tendencies of an ancestral strain are carried 
forward from generation to generation by hered- 
ity, even though unable to make themselves 
manifest for many generations, and that then, 
through some unexplained combination of tend- 
encies, the submerged trait is enabled to come to 
the surface and make itself manifest, the explana- 
tion must be admitted to have a certain measure 
of tangibility. 

Nevertheless, there is a degree of vagueness 
about the use of the word "tendencies" that robs 
the explanation of complete satisfactoriness. 

Meantime the human mind is always groping 
after tangible explanations of observed phenom- 
ena. It is always more satisfactory to be able to 
visualize processes of nature. It was for this 
reason that Darwin's theory that natural selec- 
tion is the most powerful moving factor in the 
evolution of races gained such general recogni- 
tion and still remains as the most satisfactory of 
all hypotheses of evolution. 

And it is for the same reason that a tangible 
explanation of the phenomena of atavism or the 
reversion to ancestral types has gained a tremen- 
dous vogue in recent years. 

The explanation in question is associated with 
the name of the Austrian monk Mendel, who 



SIGNS OF SUCCESS LARGER 
YELLOW- WHITE BERRIES 

From among many crosses between 
the Lawton and the old Crystal Whi^e 
a berry very much improved in size was 
secured, as shown on the opposite page, 
and the form, texture, and flavor were 
brought up to the point which made it 
almost worth growing for its fruit, 
while the color, though still far from 
white, was much lighter than even that 
of the wild Crystal White. This variety 
was a first generation cross with the 
Lawton, a blackberry, and was raised 
from Lawton seeds. 



THE WHITE BLACKBERRY 339 

made some remarkable experiments in plant 
breeding about half a century ago, and who died 
in 1884, but whose work remained quite unknown 
until his obscure publications were rediscovered 
by Professor Hugo de Vries and two other con- 
temporary workers, and made known to the 
world about the year 1900. Since then a very 
large part of the attention of the biological world 
has been devoted to the further examination of 
what has come to be spoken of as Mendelian prin- 
ciples. 

And, as is usual in such cases, unwarranted 
expectations have been aroused in some quarters 
as to the real import and meaning of the new 
point of view; also a good deal of misunderstand- 
ing as to the application of the so-called Men- 
delian laws of heredity to the work of the prac- 
tical plant developer. 

In view of the latter fact it is well to bear in 
mind that such experiments in plant breeding as 
those through which I developed the white black- 
berry and hundreds of others were made long 
before anything was known of Mendel and his 
experiments, and at a time when the conceptions 
now associated with Mendelism were absolutely 
unknown to any person in the world. It is well 
to emphasize this fact for two reasons: first, as 
showing that practical breeding, resulting in the 



340 LUTHER BURBANK 

bringing to the surface of latent traits for ex- 
ample, whiteness in the blackberry; could be 
carried to a sure and rapid culmination without 
the remotest possibility of guidance from "Men- 
delism;" secondly, because from this very fact 
the interpretation of my experiments has fuller 
significance in its bearing on the truth of the 
Mendelian formulas than if the experiments had 
been made with these formulas in mind. 

This is true not alone of the creation of the 
white blackberry, but of the similar development 
of the Shasta Daisy and of a host of other new 
forms of plant life that will find record in suc- 
cessive chapters of the present work. 

But while I would thus guard the reader 
against the mistake, which some enthusiasts have 
made, of assuming that the Mendelian formula 
about which so much is heard nowadays must 
revolutionize the methods and results of the plant 
breeder, I would be foremost to admit that the 
remarkable work of Mendel himself, together 
with the work of his numerous followers of the 
past ten years, has supplied us at once with sev- 
eral convenient new terms and with a tangible 
explanation or interpretation of a good many 
facts of plant and animal heredity that hereto- 
fore have been but vaguely explicable, even 
though clearly known and demonstrated as facts. 



THE WHITE BLACKBERRY 341 

A knowledge of Mendelism may be called the 
A B C of plant breeding, and when it was first 
advocated in America at the International Plant 
Breeding Conference in New York, October 2, 
1902, it was generally thought by those who had 
little or no knowledge of the results of experi- 
mental evolution that those who had been pro- 
ducing plants and animals of superlative value 
were far behind the times and would immedi- 
ately be outdistanced by those who adopted the 
new theory in experimenting in fact, the prac- 
tical and eminently successful breeders were 
looked upon by many of those who were enthu- 
siastically advocating the new theory as blind 
workers. Many of these theoretical breeders who 
were more or less without much practical experi- 
ence or knowledge of the results of a careful ex- 
perimental study of heredity, variation, hybrid- 
ization, etc., made many public statements of 
what they had planned and were about to do to 
secure immediate important practical results. 
Many of those connected with the experiment 
stations and others were much carried away, and 
promised to accomplish things at which the ex- 
perienced breeders could only smile until the 
awakening to the fact that nature's ways were 
somewhat more complicated than they had been 
led to believe. 



342 LUTHER BURBANK 

A paintbrush and a pot of paint never made an 
artist unless there was something more than 
theory for a guide. Extensive plant breeding 
requires for its success a very broad and exten- 
sive knowledge of botany, biology, evolution, 
physiology, chemistry, paleontology, and of the 
whole life history of the earth and its plants, a 
good knowledge of heredity, environment, varia- 
tion, adaptation, germination, inheritance, ex- 
pression, adjustment, elimination, and of hardi- 
ness, plant diseases and how to eliminate them, 
insects and how to overcome them, of soils, of the 
practical changes to be made and how to attain 
them, with a knowledge of foods, flavors, fra- 
grance, colors ; the requirements of markets, ship- 
pers, dealers, and consumers; in fact, a broad arid 
comprehensive general knowledge of the work of 
those who have gone before, and a technique in 
the work which can never be acquired except by 
most constant and careful study of the living, 
growing plants themselves, and a fund of pa- 
tience with this most enticing game with nature 
which knows no end. 

The case of the white blackberry with which 
we are at the moment concerned, is a very good 
illustration in point. 

My experiments in the development of that 
berry might be interpreted in the older terminol- 



THE WHITE BLACKBERRY 343 

ogy something like this: The big, luscious, 
black Lawton blackberry proved prepotent when 
crossed with the small brownish "Crystal White," 
and the offspring were therefore all large lus- 
cious black berries closely similar to the pre- 
potent parent. But the qualities of the other 
parent were latent in these offspring, and the 
tendency to variation having been stimulated by 
the hybridizing of these different forms the off- 
spring of the second generation showed great 
diversity, and a tendency to reversion to the traits 
of the more obscure or less prepotent of the two 
grandparents. 

In the still later generations, the conflict of 
hereditary tendencies continuing, an even more 
striking reversion, according to the principle of 
atavism, took place in the case of a few of the 
many progeny, bringing to light the pure white 
berry, a heritage from its brownish ancestor. 

THE MEXDELIAX EXPLANATION 

Now this, as I say, would fairly explain the 
case of the white blackberry in such terms as 
were universally employed at the time when this 
interesting fruit was developed. 

But the evolutionist of to-day, considering the 
same facts, would be likely to offer an explana- 
tion in Mendelian terms that would have the 



344 LUTHER BURBANK 

merit of adding a certain measure of tangibility 
to the mental picture of the actual processes in- 
volved in the hereditary transmission of traits 
through which the white blackberry was devel- 
oped. And there can be no question of the con- 
venience of these terms and of their value in aid- 
ing to conjure up such a picture, provided it be 
not supposed that the presentation of such a 
formula is to clarify all the mysteries of heredity 
and to do away with the necessity in the 
future as some misguided enthusiasts have as- 
sumed of laborious and patient experiments 
akin to those through which the triumphs of 
the plant developer have been achieved in the 
past. 

In a word, the Mendelian formulas, if ac- 
cepted at their true valuation and for their real 
purpose, may be regarded as placing new and 
valuable tools in the hands of the plant experi- 
menter, just as did the formula of natural selec- 
tion as put forward by Darwin; but we must 
in one case as in the other guard against imagin- 
ing that the phrasing of a formula may properly 
take the place of the practical observation of 
matters of fact. 

Bearing this caution in mind, let us note the 
changed terminology in which the Mendelian of 
to-day interprets the observed facts of the de- 



THE WHITE BLACKBERRY 345 

velopment of the white blackberry. His expla- 
nation would run something like this: 

When the Lawton blackberry is crossed with 
the whitish berry, all the offspring of the first 
filial generation are black because blackness and 
whiteness are a pair of "unit characters," both 
elements or factors of which cannot be mani- 
fested in the same individual; and blackness is 
the "dominant" character of the two, whiteness 
being "recessive." 

But the hereditary factors or "determiners" 
that make for whiteness, though momentarily 
subordinated, are not eliminated, and half the 
germ cells produced by the hybrid generation in 
which blackness is dominant, will contain the 
factor of whiteness, whereas the other half con- 
tain the factor of blackness. And when in a suc- 
cessive generation a germ cell containing the 
factor of whiteness unites w r ith the germ cell of 
another plant similarly containing the factor of 
whiteness, the offspring of that union will be 
white, their organisms inheriting no factor of 
blackness whatever. 

It may chance, however, that for many succes- 
sive generations a germ cell containing only the 
factor of whitness fails to mate with another 
similar germ cell and so no white-fruited pro- 
geny is produced. In such a case for generation 



WHITE BLACKBERRIES AS 
THEY GROW 

The direct-color photograpa print 
opposite gives evidence that the im- 
proved white blackberries were not only 
selected for color, flavor, size, firmness, 
and the season of bearing, but also for 
the form, hardiness, and other good 
qualities of the plant that bears them. 
In the final production of any new fruit, 
all of these qualities and many others 
must enter into consideration and a 
perfect balance or combination of all 
of them is the triumph of final selection. 



THE WHITE BLACKBERRY 347 

after generation the white factors continue to be 
produced in the germ cells, but the union with a 
germ cell containing the black factor obscures the 
result just as in the case of the first cross, because 
the factor of blackness continues to be dominant. 

But, however long delayed, when a cell con- 
taining the white factor or determiner does mate 
with a similar cell, the offspring is white and in 
the older terminology reversion or "atavism" is 
manifested. 

A very simple and tangible illustration of the 
phenomena in question is furnished by the ex- 
periments in animal breeding made by Professor 
William E. Castle of Harvard. These experi- 
ments furnish a peculiarly appropriate illustra- 
tion in the present connection because it chances 
that the animals experimented with are compa- 
rable to our blackberries in that they are respec- 
tively black and white in color. 

The animals used in the experiment are guinea 
pigs. 

AN ILLUSTRATION FROM THE ANIMAL WORLD 

Professor Castle shows that if a black guinea 
pig of a pure strain is mated with a white guinea 
pig of a pure strain, all the offspring of the first 
generation will be black; and it is therefore said 
that blackness is preponent or dominant, and 



348 LUTHER BURBANK 

whiteness recessive. But if two of these black 
offspring are interbred, it is an observed fact 
that among their progeny three out of four indi- 
viduals will be black like their parents and one 
of their grandparents, and the fourth one will be 
white like the other grandparent. 

The Mendelian explains that the factor of 
whiteness was submerged, dominated by the 
factor of blackness, in the second generation; 
but that half the germ cells of these black indi- 
viduals contained the factor of whiteness, and 
that by the mere law of chance the union of these 
germ cells brought together about one time in 
four two of the cells having the recessive white 
factor; such union resulted in a white individual. 

Meantime by the same law of chance the other 
three matings out of the four brought together 
in one case two black factors and in two cases a 
mixture of black and white factors. 

As black is dominant, these individuals having 
the mixed factors would be individually black 
(just as those of the first cross were black) ; but 
their progeny in due course will repeat the 
formula of their parent by producing one white 
individual in four. 

It should be explained that the Mendelian, in 
expressing this formula, usually substitutes foi 
the word "factor," as here employed, the newly 



THE WHITE BLACKBERRY 349 

devised word "allelomorph," although the less 
repellant equivalent "determiner" is gaining in 
popularity. He calls the body substance of an 
animal or plant a "zygote," and he describes an 
individual that contains factors of a single kind, 
as regards any pair of unit characters (say only 
for blackness in the case of our blackberries or 
Professor Castle's guinea pigs), as a "homo- 
zygote"; contrariwise a body having both types 
of factors (blackberries or guinea pigs of the 
second generation, for example) as a "hetero- 
zygote." 

But these big words, while it is convenient to 
know their meaning, need not greatly concern 
us. It suffices to recall the convenient terms 
"dominant" and "recessive"; to recognize that a 
good many antagonistic traits may be classed as 
unit characters; and to welcome the conception 
of the division of the factors or determiners of 
such a pair of unit characters in the germ cell, as 
enabling us to form a tangible picture of the 
modus operandi through which the observed 
phenomena of heredity may be brought about. 

MIXED HERITAGE OF THE BLACKBERRIES 

It remains to be said that the case of our black- 
berries is a little more complex than the case 
of the guinea pigs just referred to, because there 



350 LUTHER BURBANK 

is a second pigment involved. The "Crystal 
White" berry, it will be recalled, was not white 
but brownish in color. There were thus trans- 
missible two pairs of unit characters involved as 
regards the matter of color, namely ( 1 ) black ver- 
sus white, and (2) yellow or brown versus white. 

The black factor or determiner dominated 
absolutely in the first generation; but in the 
second generation a certain number of germ cells 
were paired in such a way as to eliminate the 
black but retain the yellow factor. 

It required a third mixture of the germ-cell 
factors to produce a union in which neither black 
nor yellow factors appeared, the offspring of this 
union being of course the pure white blackberry. 

The presence of the yellow factor accounts for 
the further fact, to which reference should be 
made, that there were various intermediate types 
of berries, neither black nor white, which ap- 
peared in successive generations but which are 
eliminated by selection as they did not fall in 
with our plan of development of a white race. 

The explanation just given makes it clear 
that, once a union of germ-cell factors having 
only the white element was effected, the black 
and the yellow factors being entirely eliminated 
from that particular individual, the germ cells 
arising from that individual would necessarily; 



THE WHITE BLACKBERRY 351 

contain only the factor of whiteness; hence that 
all the progeny of that individual would breed 
true and produce white berries. 

Such is indeed the observed fact with my de- 
veloped strains of white blackberries. Grown 
from the seeds, these breed far truer to their 
parentage than is the case with most cultivated 
fruits. As to certain other qualities they may 
vary, but all are white. 

The Mendelian explanation obviously cannot 
add any force to this observed and long ago 
recorded fact. 

But it does serve to explain the observed fixity 
and permanency of the new and anomalous 
breed. It enables us in a sense to understand 
the paradoxical fact that a berry having a whole 
galaxy of black ancestors may have no strain of 
blackness, no tendency to reversion to the black 
type, in its composition. 

But we must not put the cart before the horse 
by supposing that the new explanation adds any- 
thing to the force of the previously observed 
facts. Hypotheses are for the interpretation of 
observed phenomena, not phenomena for the 
interpretation of hypotheses. 

One other word in this connection. To would- 
be plant experimenters who ask my opinion of 
matters connected with the old versus the new 



352 LUTHER BURBANK 

interpretations of heredity, I am accustomed to 
say: 

"Read Darwin first, and gain a full compre- 
hension of the meaning of Natural Selection. 
Then read the modern Mendelists in detail. But 
then go back again to Darwin." 

Bear in mind Professor J. M. Coulter's com- 
ment that "Mendelism has extended from its 
simple original statement into a speculative 
philosophy," and try for your own satisfaction 
to separate the usable formula? from the intricate 
vagaries of the new creed of heredity. 

Let me cite a recent assertion of Professor 
William E. Castle, himself one of the foremost 
experimenters along the lines of the newest 
theory: 

"As to how a new race is begotten we have not 
got much beyond Darwin; indeed many of us 
have not got so far." 

The man who has got as far as Darwin in the 
matter of understanding racial origins to say 
nothing of getting beyond him even in our day, 
is no tyro in the study of heredity. 



Read Darwin first; then read the 
modern Mendelists; and then go 
back to Darwin. 



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